MacBook: Won’t start, flashing sleep light

If you turn on a MacBook when it’s completely powered off (not sleeping), and instead of starting up, the screen remains dark and the sleep light is blinking, the MacBook’s RAM might not be installed properly or might have worked loose. I found this out when re-seating the RAM of a friend’s MacBook to try and fix a problem. I thought I had pushed the RAM modules far enough into their slots, but after the MacBook failed to start up I took another look and found out that you really do have to push firmly and carefully past some initial resistance until the RAM goes in all the way. You may have to push harder than you think is normal, but seriously, you have to push pretty hard.

If your MacBook has metal levers near the RAM, don’t use the levers to do this. The levers are only for popping out the RAM, not inserting it.

I wasn’t able to find a tech note at the Apple site about this, and that’s why this entry exists. In case it helps someone.

(Update: It seems like this applies to newer Macs such as the unibody aluminum MacBook Pro line and the iMac, although I haven’t tried it myself. However, it won’t work with a MacBook Air or a MacBook Pro with Retina Display, because on those models the RAM is permanently soldered to the motherboard.)


  1. Thanks a million for that, I ran into the same problem and was quite upset until I read this. You actually have to push til it hurts 🙂

    1. I love you. I have had such an awful day and this saved my life. Okay, dramatic, but seriously, so so glad I found this.

  2. Thank you so much!!! Like all the previous posters, I too had the exact same problem (thanks for the tip on required force, “Scott”).

    After only two days of having my MacBook, I was frekaing out when I ran into this prob…about 15 mins of Google searching led me to this post…thanks a mil!

  3. Hey man, thanks a lot; great tip 🙂
    My Macbook caught Random Shutdown Syndrome recently, and part of the process in getting Apple Phone Support to set up a repair was reseating the RAM. Needless to say, I didn’t push the memory back in hard enough and later that day; the computer refused to start.
    What I noticed with the L-bracket was that the spaces between the screws bulge out very slightly when you don’t have the ram chip push far enough.
    Thanks again!

  4. Dude you are the man…

    I took out the HD just to check it out and when i put everything back together i thought i broke the HD or something fucked up! I was pissed i guess i must of bumped the stupid levers!

  5. This is what I love about the internet-
    I Google “Macbook flashing light” after trying to install 2gigs of Ram into my Macbook, and I end up here. I follow the directions, temporarily disfiguiring my index fingers, and – Awesome!
    It worked. Whoever you are, it’s people like you that make my day.

  6. Wow , do they take a lot of pressure to seat !
    Word of caution .
    I tried to tuck in the groundig mesh with my finger tip & sliced into it like a razor blade. Be careful & use a tiny screwdriver .

  7. Thanks so much for posting this!! I’ve found myself in exactly the same situation as you all. The take home message is that you have to push the RAM in really very hard. Thanks for giving me the confidence to push harder!

  8. I tried it twice till my finger hurt and am still getting only the flash. I called Apple support and they said there was nothing they could do by phone. They recommended I take it back to the store I bought it from. Any you guessed it. It worked fine there. The tech got it boot up the first time and every time he tried it. I was able to start it right up myself several times. But, when I got it home it started doing it again. Frustrating. I have been a PC used all my computer life, and decided to make the switch after having to put up with Windows. Now I not so sure I did the right thing. At least I could always restart my PC. When I have got the computer to start, I have it freeze up as much if not more than the Windows did. Have not been that impressed with the Mac!

  9. YetAnotherThanks! I put more RAM in, and it worked. Just luck I guess. But when I put in a bigger disk it got flashing sleep LED syndrome. I thought the disk was bad.

    A little pushing on the RAM made the disk work.

    Made that L-bracket look better, too…

  10. Follow up on my MacBook problem:
    I did an update of the software and it has eliminated the problem of the flashing light. Also, I haven’t had it lock up.

  11. Oh my god, thank you!

    After installing my memory the first time, the computer did start up ok, so I was happy. However, when I retstarted the computer, it would not start up again and I received the blinking light.

    I attempted to reseat the memory without any luck until I read this post. I pushed and pushed and tried again, still no luck. The third time I pushed until I thought I would push the memory out the other side. You literally have to push until the tips of your fingers *hurt*.

    My computer is now back up and running.

  12. Just like all the others who posted here I just wanted to tell you how much I appreciate your post: So if you ever come to Denmark, look me up and I’ll buy you a beer or two 🙂


  13. I’m having lots of problems putting my new 2 1 gig ram sticks in and i guess i put it in not right. Im trying to take it out again but its stuck now! It’s really frustarating. Could somebody please help me? I really don’t want to take it to the apple store to just me $200 for just a simple thing.

  14. I’ve put so much pressure on the 2 1 gig sticks i’ve been trying to install, almost to the point of my fingertips nearly bleeding and I still can’t get my macbook to start up. The memory sits in the slots fine, and both are at the same position so I don’t see how they aren’t installed. Argh this is making me want to pull my hair out.

  15. OH MY GOD THANK YOU SO MUCH FOR THIS POST. I have now completely disassembled my macbook. pulled everything down to its bones off. My harddrive just quit on me and i was afraid i broke it even worse. thank you so much again.

  16. Thank you for the post; I really appreciate the guidance! I thought maybe I broke the slot itself or something. The MacBook was quite an investment for me, so my heart SUNK when the light started blinking. :S I read your site and decided to “…try it one last time,” and I am so glad I did! Thank you again for your help!

  17. Dudes you have really impressed me, i thought i stuffed the memory and also my macbook, i pushed really hard and knowing how mac products are i thought i would break the thing, but it works.

  18. Well my Macbook just flashes the sleep light. It isn’t even restarting now. I had very little problem except for the begiining few weeks last year with my macbook. It worked beautifully until this week when it kept asking me to restart. and yesterday it refused to do that. What do you think could possibly be wrong with it. I know I had a few kernal panics. But I thought it would be just an installation problem. Now it isn’t working.

  19. I bought 2X1 GB RAM for the 13″ macbook and could not push it in with my fingers. I did have success using the hand mixer beater from the kitchen drawer though! My wife held the macbook and I, using a chamois cloth, pushed with the back end of the beater part pushed it in. I will tell you I tried many times with my fingers to no avail. This method popped it right in. I started on one corner and then slid it down and repeated till it was in. IT WORKS NOW! i can swap back and forth from parallels/XP and all my mac apps at the same time w/o any lag. awesome!

  20. Wow. I almost died thinking I killed my computer. If not for your comment about really having to push in the memory, I might have sent my computer to repair. Thanks for the tip about seating the RAM.

  21. Another person saved by this info. I agree, this needs to be posted on mac support. I wasted a day trying to figure out why my computer went to sleep and wouldn’t wake up.


  22. This is a lifesaver for me, just installed 2Gig of Corsair memory. Turn the Macbook on, nothing but a flashing light. I thought I was screwed, so I went to install the original ram. back in, turn it on, same thing. Now I can go to sleep.

    Thank you very much.

  23. Just to add my own thanks. After surviving RSS, battery problems and overheating, I thought I’d finally killed my machine off when I turned it back and saw nothing but that flashing white light. Panic over, RAM safe and snug.

    You’re a lifesaver.

  24. I tried this and the only thing I’ll say is that if you think you’re not pushing too hard on the RAM, you’re not! OMG, you’ve really got to give it a good shove. I think I ahve to get a finger tip reconstruction now! Thanks man, great post.

  25. Just another quick thanks. Funny that it was even running at all b/c i put in the extra RAM about 4 months ago, and just today it went all blinky on me.

  26. Yet another vote of thanks from me – now up and running thanks to this advice. But yes, you really DO need to push very hard!

  27. Hey thanks a ton.
    I thought that i was screwed when both my 1gb and 2gb had the blinking light.
    You try to be careful with the memory, but in actuality you really have to shove it there.

  28. the immediate availability of acutely needed information such as this and the wonderful spirit of people that want to make it available freely are two reasons why the internet is great and beautiful!

    so thanks for saving me from an impending sad face saturday!!!

  29. Having upgraded PCs all my life, I knew that you have to be aggressive with memory.

    Installing the 2 Gigs of RAM in my BlackBook and when it wouldn’t come on, I thought I had some faulty memory on my hands.

    Woah, you really have to push until it sits in, thanks for the tip.

  30. I’ve had this problem in even older computers, not just MacBooks. iBooks, iMacs, etc. do the same thing. You do have to push HARD! I was afraid I’d break the card before I got it to start!

  31. If you ever see white crude on the contacts of your RAM…it really is lubricant…because I guess they didn’t allow enough room for a good fit with out the lubricant…I thought it was battery corrosion…but APPLE tech told me it was lubricant….my chip fell out after working fine for months…right after I upgraded to 10.4.11…needless to say I thought it was the upgrade…but checked seating JUST IN CASE and voila that is what it was…I had never really seated it ….properly in the first place…just lucky it actually worked with it bearly touching the contacts…it took a real push to seat it.

    I see from reading here I am not alone.

  32. Cheers!!!! My heart stopped 4 times had 3 mini-strokes and lost half a head of hair till I tried your trick…..I have sore fingers but at least I haven’t lost all my years work of research. This is a great tip!!! I guess no pin…no gain 🙂


  34. thank you! I upgraded my RAM on my MacBook and thought I”d really lost everything when it wouldn’t turn on!! INitially it did turn on but only 1 of the RAM modules showed up, so I opened it back up and reinserted them both and then NOTHING!

    I think the really key tip to knowing if you’ve pushed in far enough if what someone said up top–if the metal cage thing is bulging in between the screws, then you need to keep pushing–and like someone else said–so hard that it hurts!.

    Thank you so much, glad I found this site–now I’m happily upgraded and running! Why in the world don’t the manuals/directions say all this stuff. All theApple direction that I got online from were that you should not see the green edge popping out, but that wasn’t such a specific cue.

  35. Awesome! My heart sunk after I put some new RAM into my Macbook and turned it on only to get a flashing sleep light. A quick search on Google and I came across your tip. Saved me a trek back to the Apple Store.

    Has Apple offered you a job yet?

  36. Just to let some people know, I struggled with this for hours as everyone else did, and in the end, after breaking the RAM board, talked to an Apple Genius only to find that my computer’s motherboard can only handle 2GB of RAM total, despite the 2 slots. Might be worth checking that out. I bought my computer in the early summer of 2006.

  37. THIS WORKED FOR ME TOO!!! My RAM upgrade was working for a while. Then I started getting random crashes and sometimes my computer wouldn’t boot. At first I thought the RAM went bad, so I got new RAM. Still didn’t work, so I was quite bummed that something might be wrong with the motherboard.

    Just found this article today and gave it a shot. What do you know! It worked! I am surprised my laptop worked at all before I pushed the ram all the way in.

    And a little tip for other people, use your nails to push the ram, not your fleshy finger tips. No pain pushing the ram in at all 🙂

  38. Thank you SOOOO much! I was panicking already when I found this post, and quickly realised I hadn’t pushed hard enough (you REALLY have to push till it hurts!). You’re the man 😉

  39. push till it hurts? I am having a hard time here also. i dnt feel like it can go anymore! now none of the ram starts the computer!

  40. thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you

    I thought I had fried my Macbook.

  41. Hey, above posters having problems. First off, it actually all of a sudden gives a little when you’ve pushed hard enough, right at the end. And if the gasket seems like it doesn’t fit quite right, it means you *still* haven’t pushed in the RAM far enough. It seems like it’s in. It’s not. Push harder. Keep going. Eventually, it goes in a tiny fraction of an inch further.

  42. This page was a life-saver! jhn is right – I thought the RAM was in. Thanks to the tip to “push ’til it hurts”, it’s fixed. And one really does have to push harder than I’d ever have felt safe doing.

  43. Hi!

    Thanks so much for this.

    Just ran into the same problem… you really do have to push quite hard.

    I found the tops of my fingers hurting (:


  44. mine just had the same problem, I took it to MacHouse in Amsterdam. Firstly the guy shaked the laptop (for god knows reason) in case there was a bug inside? (at that stage am questioning in my head whether those guys know what they are doing)…then he went at the back to test with other memory to find out that it still didn’t work…so for me looks like its the logicboard… my 2nd one in 19 months, does Apple test their product or do we at our expenses?!

  45. Thank you!
    I almost given up the hope of getting my macbook back in life, sleep light turns on permantly, but after your tips all getting back to normaly, thank you again!

  46. Hey, good tip. But if this were the case then the RAM wouldn’t show up in the OSX control panel, right?
    Email me if u know something!

  47. Thanks for this post. This helped fixed my daughter MacBook today. She replaced RAM a long time ago but for some reasons they came loose and after trying everything I found this post and reset the RAM and it boot up. Thanks again.

  48. Hey,

    Thanks so much for this post. For anyone in this situation, you really do have to push HARD. My fingers hurt now, but my MacBook is working!


  49. thank you!!
    and just as a side note, if it hasn’t already been pointed out. using a credit card (or some kidn of car) to push in those foam supports will help a lot when puutting back on the metal frame.

  50. hi all

    sometimes you do have to push quite hard, but if you have to push REALLY REALLY hard then maybe you aren’t doing it right…

    it’s important to install the board on an angle, it should push almost all the way in on an angle, then drop down into place… if you lay the board flat and try and push it horizontally then it can be very hard!

    some finesse is required!

  51. I bought a 2 gig stick for my Core Duo MBP. Afterward I read my comp could only support 2 gigs total, but no big deal. After drilling through the head of a stubborn screw (that screw pissed me off so much) and installing the new stick I got the flashing light syndrome. Found this article, pushed the stick in and got rid of the flashing light but the computer still wouldn’t start up. I removed the original 1 GB stick and replaced it with the 2 GB stick and now my computer works. Just putting it out there for anyone with the same problem.

  52. It’s amazing how helpful a small piece of information can be, and how long it can remain useful. I see you posted this in 2006 and two years later it’s still helping people.

    30 minutes with Crucial’s Live Support with no resolution…2 minutes doing a Google search, finding your post, and fixing my computer.


  53. Thanks, it worked. I was panicking because I replaced the top case (spilled wine on keyboard) and the macbook wouldn’t turn back on. Reseating the memory a few times fixed it!

  54. There were some cold and dark lonely days without my trust albino friend. Today you bought him back to life. I love you.

  55. WOW It worked, can you imagine a thread that started in 2006 still being useful in 2008! Saved me from an all nighter. Thanks again!!

  56. everyone was pointing at software, motherboard etc issues. who’ld a thunk? you MUST be old school!

    in the old days we would drop the device on a table to reseat shit

    you rock, man!

  57. My husband was FREAKING OUT because he thought his computer was toast. But, after I found this thread, he tried it, and it worked. Thank you guys so much!!!!!

  58. thank god for you, and for my phone having a web browser. I found this in seconds from google, and it completely saved my life.

    Side note: I also received a loud beeping tone with my flashing light and non- working computer.
    Pushing harder completely solved this problem.
    … and saved me from a panic attack.

    seriously, god bless you.

  59. Thanks for your help! I pushed it in all the way until it hurt and now my computer boots up again. Thanks!

  60. AMAZING!!!! I nearly lost my mind.. and cried a lil bit. but YAY!!! It worked. I don’t know you but heres a virtual hug!!!!!!!!!

  61. I would like to confirm this applies to iMac’s too (mine was an Intel 17 inch). RAM was the issue and fixing that allowed the system to boot afterwards! Thanks!

  62. i have the same problem, and googling it sends me here.
    it works exactly, and I am impressed this tip worked for so many people many years after it was first posted.

    well done, bro. good job.

    my macbook is up and running good again!

  63. I’m going to try that again and see if it works for me….I took my macbook to apple store the first time it happened and then the flashing light and 3 beeps came back in two weeks again!!! I wish apple can recall this problem…it is SO frustrating!

  64. The pushing hard part is what got me. I found that if you use both thumbs on the left and right side of the chip you can force it into the slot.

  65. Thank you so much for this. I have been struggling all day to get my macbook to boot up and tried all the mac help tips and googled info I could find but to no avail. This worked a treat and I had to push it in even further than I thought it would go in – thank you so much, you’ve saved my bacon!!

  66. I was one of the many (it seems) who had the non-boot problem after replacing the original RAM with 2 x 1 Gig cards. I have spent 3 days typing all manner of Search entries into Google and “imac & flashing light” did it. Your advice regarding the neccesity of pushing really hard was the answer. One is generally reluctant to use brute force with precision parts but on this occasion it is necessary. Thanks so much.

  67. This thread still working for people. Was about to ditch 2-year-old MacBook thinking it had died. Add my thanks to this long list.

  68. Worked like a dream!!!!! I’ve suffered with start up problems with my Blackbook on and off for 6 months. I live on a cliff tops on the south coast of England and I was getting very close to chuck the bloody thing over the cliffs into the sea! But this thread means my Mac lives on! Thank you guys!!!!!!!!

  69. “macbook pro ram install now light is flashing”

    this is exaclty the most random phrase i googled and up pops this site. gave a little extra muscle like you said and voilà- i have a 4gb macbook pro. I LOVE the internet and people like you who take the time to post this info!!!!

  70. Thanks for that- I haven’t actually tried it yet, but that’s exactly the problem I have and none of the other problems written about match it this well.

  71. Thank you so much for this tip! I was getting really frustrated trying to figure out what was going on and luckily found this article on my iTouch. Thanks again! Saved me a lot of frustration!

  72. I was absolutely despairing when the light was blinking madly! I thought I’d ruined the Mac by pushing the RAM in too far. Turns out it wasn’t FAR ENOUGH!!!

    Thank you so much for this tip and giving me the courage to push further! I’ve now updated the RAM and installed all my new programs as a result, all thanks to you!!!

  73. Thank you SO SO MUCH! after installing a new hard drive and CD drive i thought the worst was over until i saw the blinking white light and almost went into cardiac arrest. thank god it was just an issue with not pushing the RAM in far enough!

  74. This was my problem too. I had a feeling it might not have been seated properly, but I wanted some assurance before I pressed to hard and broke something!

  75. Worked like a charm! I had no clue, since my MBP15 battery was replaced by Apple service centre, why the hell on earth the MBP is shutdown abruptly and blinks while start!?!?
    Thanks a lot.

  76. Thanks a ton… after a complete fail in a iBook upgrade I was afraid I had killed another machine. Feeling much better now.

  77. omg u just saved my life!!! i just upgraded my mbp hard drive and thought i screwed up completely but it was just the ram !

    thanks a billion!

  78. HOLY FREAKING COW i’m so glad i found this blog!
    this was exactly my problem.

    i was replacing my husband’s RAM and he is leaving on a trip (with the MBP, of course) and here I am, starting to freak out.

    your instructions and comments worked like a charm! phew!


  79. Trying to resurrect my old macbook for my 5 year old daughter this Xmas eve (a mac is top o’ her list to santa) – I must have popped the ram out a while back for some reason. You guys saved the day! Exactly what I needed to know this late hour. Thankyou!

  80. I was having the exact same problem and apparently wasn’t pushing the memory in far enough. After I read this I’m back in business. Thank you so much for this help!

  81. I had to take out my keyboard (and on the way the ram and hard drive and so on) after one of my kids spilt water all over the keyboard.
    24 (drying) hours later I was feeling pretty vulnerable as I reached for the power button and the blinking sleeper light wasn’t the best thing I’ve seen this week.
    I’m glad I accidentally typed my query into the address section of Firefox because it came straight to your site (unlike when I repeated and typed into the right hand window) and even then I didn’t press the RAM in hard enough. We’re all taught not to force, aren’t we.
    So it still didn’t work and I was getting ready to send it in to the repair shop when these words bounced back into my head “You may have to push harder than you think is normal, but seriously, you have to push pretty hard” and I undid the L bracket and had another go. Damn, you made my day. My only (positive) criticism: maybe italicise or underline those last three words.
    I’ll be directing traffic your way with pleasure.

  82. Does anyone knows how to do this with a MacBook Air. I have the same problem, the flashing light and the 3 beeps that repeat themselfs. The guy at the apple store told me my RAM is in my motherboard so I will need a reperation of 500 euro’s. I’m dying right here!!! Can’t believe this..

    1. I don’t think the solution in this blog post will work with a MacBook Air. From what I am reading on the web, the RAM in a MacBook Air is permanently soldered to the motherboard, so it can’t be removed or replaced. The tip in this blog post only works with MacBooks with replaceable memory. Sorry…I think the most realistic solution is to find an authorized service center that will charge less money…500 euros seems like a lot!!

  83. thanks for this post!

    I just replaced the hard drive in my 1st gen. 2007 macbook pro and after a long tedious process, the computer wouldn’t start and the sleep light was blinking. i had removed the ram in that process just to be on the safe side, but hadn’t properly reinstalled it (by snapping it in completely) and i got the blinking light. my heart sank and i didn’t know what was going on until i found this post. i re-checked the ram and and that was precisely the problem. THANKS!

  84. thank you so much… yes, push hard to install the memory to the slot, finally, my mbp just back. Thank you so much

  85. Thanks. Just installed new memory in my old MacBook pro and had this symptom. Went band and checked that I had pushed the little fellas in as far as they could go and mow we’re back in business.


  86. Whoo Hoo! This post was a life saver. I upgraded my MBP’s hard drive and somehow managed to knock the RAM loose in the process. I was really worried I had fried my laptop. After reading this post, I looked at the RAM module and noticed I could see the gold contacts sticking out of the slot. I completely removed the module and shoved it back in until it was properly seated (could no longer see the contacts) and viola it boots like a champ!

    Thanks a million,
    Avery Davis
    Atlanta, GA

  87. This worked for my iMac, too! The key: “You may have to push harder than you think is normal, but seriously, you have to push pretty hard.” Thank you!!

  88. I was trying to upgrade my hard drive, but the new hard drive would not work. So, I reinserted the original drive, but now it was not working.
    You idiot, thought I, now you are going to have to take it in and pay a fortune.
    But, just in time, I stumbled across this site. Off came the L bracket. ..pushed in the ram…two clicks indeed. It worked!
    Much much thanks.

  89. OMFG thank you so much man I was pissed but I was google searching and it led me here now my MacBook is running great.
    Thanks if I could I would pay u lol

  90. Looks like you’ve helped a LOT of people here! Thank you
    for this, I was really worried that I’d screwed something up big
    time. Viola! It works just like you said.

  91. Thanks a bunch, man, I never had problems in the three years since I owned my macbook, and when this happened I panicked like the rest of the people posting here. You have saved me time, money, and most importantly, my computer.

  92. Thank you thank you thank you 🙂

    All kinds of weird crap was happening – seemingly random shutdowns / reboots / screen flickering / horizontal lines / keyboard & mouse not responding… And now *everything* seems to be working awesome.

  93. Ive tried pushing in the ram as hard as possible, but i still cant fix my issue.

    The screen flashes for a split-second, then i get the blinking light.

    I kept only one RAM slot occupied and the light stays solid, but still no screen.

    Any suggestions???

  94. Just like everyone else, I am thankful.

    Have been dealing with this for months and never stumbled across this.

    …you are…the man..

  95. Oh my God!

    This must be the most useful tip in the whole world! When my -already worn out- MacBook Black refused to start up once again, after a dodgy journey from Brussels to Nantes, I was ready to sell it away as spare parts and wanted to buy myself a lousy iPad2. Ten minutes later, thanks to your post, I’m writing this message on my reborn MacBook! For free!

    Fantastic! You rule!

    Seb from Brussels.

  96. Your post just keeps on giving! I love you!

    I thought it was game over for my mac and switched old and new memory in and out several times, but still couldn’t get anywhere. But your genius post is correct – you’ve just got to press in the RAM cards unnaturally hard and they will nudge in one bit further.

    Now I can get another years use out of my tired old MacBook v1.

    All hail Conrad Chavez!

  97. u just saved 2 of my macbooks. ur a godsend. i always thought i was pushin tem in enough n bout to get another macbook. mine have served me well. now i gt both working. i should go back to my old ibook n check it. thanks

  98. Thank you so much! Its amazing how much this helped my day. Whoever you are, I really appreciate it!

      1. I recently upgraded the ram on every mac in my household. Had a whole process going, 6 macbook pros (big family), Three of them failed the next day, and this post, I swear to all that is good, saved me thousands of dollars 😀
        I cannot begin to tell you how thankful I am!

  99. “You may have to push harder than you think is normal, but seriously, you have to push pretty hard.”

    Not if your doing it right you dont have to push hard.

  100. I also had this same problem. I was upgrading my 2.4 17″ macbook pro from 2 gigs RAM (1 gig per card) to 4 gigs RAM (2 gigs per card). After installing I had the same issue with the led light flashing but no boot. After finding this forum I pushed the cards very firmly as stated, to no avail.
    After calling tech support of the memory manufacturer I was asked to try each card individually. With one installed the computer booted properly with 2 gigs being recognized. The other card did not and flashed the error light. It seems as though one of my cards was defected and the system wouldn’t load with both installed, even though one was working fine. I’m receiving a new kit and hope to have better results. Hope this helps anyone who hasn’t had luck with the above fix.

  101. Thanks..after 5+ years this tip saved my butt. Sister in-law’s computer with her Phd thesis on it, I thought i was a dead man until i found this…thanks

  102. TLDR: Remove power and battery, hold power btn for 5 seconds

    While the memory re-seating is a good notion, it didn’t work for us. What did work was carefully following the support article:

    Intel-Based Apple Portables: Troubleshooting a computer that will not power on

    Specifically resetting the SMC:

    This device apparently controls a lot of low level lighting and the boot process. Our problems started after the laptop drained its power and shut down, e.g. the first cold boot in weeks.

    Following the instructions we unplugged the power cable, removed the battery, and held down the power button for five seconds.

    After that, it booted fine.

  103. Oh my goodness thank you for this. I was having a mini freakout! Why don’t the apple forums recommend this first? They all get so technical, but this is exactly what I needed. Thank you!

  104. omg you saved me! i’d only spilled a few drops onto my keyboard, killed the laptop in a little village in the middle of nowhere with no car and no mac store and took the entire thing apart, cleaned it with a camel eyelash paintbrush for hours, put it together and it didn’t work until i saw your post! thanks a million ❤

  105. thank you so much. i thought it had pushed them in as hard as possible. i redid it pushing until my fingernails cracked and my fingers bled, but it worked. ridiculous. but thanks!

  106. Wow, it really needs a real hard push. Apple always have to make it unique . and that pain in the butt L bracket with its tiny screws I had to screw unscrew three times. thanks for your blog post and tips!

  107. Just to add, i couldnt fix it by pushing in on the ram, it wasnt enough. But the blinking stopped when i tried charging from another power socket. it still wouldnt power on, and then i just tried holding the on switch for 10 seconds, and it booted up.

  108. Today after putting my macbook to sleep by closing it, it wouldn’t wake up from sleep but it did have that flashing light. So I tried switching it off by pressing the on/off button. My laptop’s now switched off but now I’m having troubles turning it on again. How do I solve this?

    1. Hi veron, I’m not sure if that’s the same problem talked about in this post, but I’ll try to think of some possibilities.

      One possibility is that the RAM modules inside the computer have gotten loose. That might explain why it used to be fine before, but not now. If that’s the cause, you could push the RAM in more tightly as described in this post.

      Another possibility is that a certain area of your Mac’s memory (different from RAM) might need to be reset. If that’s the cause, you might be able to fix it by following the directions under “Resetting PRAM and NVRAM” in this Apple tech note:

      Another idea is that there might be a loose connection somewhere inside the MacBook that’s preventing the power button from working properly. If that’s the cause, you’d have to take it in and have an Apple (or Apple-authorized) technician look at it.

      Again, I’m not sure what the exact problem is that you’re seeing, but I hope these ideas put you on the right track!


  109. Worked! Thanks so much for the advice! i went to the Apple store who told me that it was the screen that didnt work.
    But after i pushed the RAM hard back in, it works perfect again.
    Another bear to you if you come to Denmark ..

  110. /me too. My 2009 MacBook arrived with the ram unseated, faied POST as soon as I unpacked it. Periodically repeats, even to the point of getting replacement RAM at the Apple Store. This flashing light business was new, and comes right in between two disk failures, full on format/restore events, in 24 hours.

  111. THANK YOU SO MUCH. Spent hours figuring out which combination of RAM cards would work with my early 2006 iMAC. (Turns out we had purchased too much – got it figured out finally.) After that struggle, you can imagine my frustration when I got the persistent blinking light, knowing I was so close to resolving my problem. SO GLAD I finally wrote the correct combination of search terms such that this came up at THE TOP of Google’s search results. YOU GET RIGHT TO THE HEART OF THE PROBLEM. I like your statement, “You may have to push harder than you think is normal, but seriously, you have to push pretty hard.”

  112. O wow, what an incredible piece of information. I’ve not been using my MacBook for months, saw this post by accident and though id give it a try just in case. It worked! Thank you thank you thank you!

  113. This page saved my old Macbook from the trashbin !!!
    I spend a lot of nights trying to fix my not working Mac, and it seems like no one could help! … I even bought a new mac 2 Month ago! Now, I tried it once more and found this page and now…
    I have the old Mac working again !!!
    Thank you so much…

  114. Thanks a lot my dear friend for sharing such a magical post. I did it and got my mac book pro back.. 🙂


  115. Thank You so very much, I thought I was going to have to get a new computer. I just had to shove it intil it thumbs hurt.

  116. MacBook plugged in there I’m wearing 2g ram 1gb ram slots empty in the other slot What do I do once the sound coming from my faulty ram does not gre keyboard

  117. Just a note for 17inch Macbook pro users, the RAM on these doesn’t slide straight in. Put in place on the angle then the Ram assembly pivots and locks the whole thing flat. Not too much pressure is required to make this happen. It fooled me at first.

  118. after years of posting the solution, it still continues to be extremely useful. i cannot thank you enough. i had wasted the whole day and was really worried about the data that I had not taken any backup of.
    Thank you so much. Best wises

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