The Tallyn’s blog has posted a list of error codes you might see in Canon digital SLRs:
Canon Error Codes Revealed
What, no Error 99? (Actually, the post says the list is for the 5DMkII and later models.)
If paper doesn’t feed through your Epson printer, look out for the following:
Leading edge problems. If there’s anything wrong with the leading edge of the paper (the edge that goes in first), the printer may not be able to load it. Check for creases, folds, tears, or other damage. Proper loading depends on the leading edge being perfectly even, so that it goes straight into the rollers. If the leading edge is damaged, try turning the paper around and loading the edge on the opposite side instead. If for some reason that’s not practical, do your best to smooth out the edge. This problem is more likely to happen with paper that was reused or damaged.
Paper curl. If the paper curls the wrong way (outward compared to the rollers), the printer rollers might not be able to grab it. Remove the paper and see if it has a curl at the edge. If it’s printable on both sides you can try printing on the other side so that the curl goes the other way. If it’s coated on only one side, you’ll have to carefully try to de-curl it. If it’s expensive fine-art paper, use great care to avoid creasing it or leaving fingerprints when you try to remove the curl. The expensive solution is to use a deroller; this is typically used by people who buy paper in rolls since those tend to make the curl quite persistent.
Friction with other sheets. If you’re loading multiple sheets at a time, the frontmost sheet might not drop into the rollers if it sticks a little to the next sheet in the stack. Try jostling and fanning the paper stack to loosen them up. This is more of a problem with papers with some types of coatings and textures.
Dirty rollers. House dust or dust from matte or rough fine art papers can build up on the rubber rollers, reducing their grip and making it harder for them to grab the paper. If a cleaning sheet is available for your printer you can try that. If you don’t have a cleaning sheet, try picking up the dust off the rollers by pressing a piece of moderately sticky paper on them. (Don’t use something that’s so sticky it might ruin the rollers, like packing tape, address labels, or duct tape.)
If the printer continues to have trouble grabbing the paper, as the print job starts try holding the paper and give it a slight nudge in as it loads.
Narrow paper. On the Epson Stylus Pro 3800, the manual feed slot doesn’t like paper that’s much narrower than a US Letter sheet. You’ll have to feed it through the automatic feeder. But the automatic feeder may have trouble with paper smaller than 4 x 6 inches; you may have to keep it straight with your hands as it drops into the slot.
Black area of paper. On the Epson Stylus Pro 3800, there’s an odd issue where the Epson 3800 may not sense the paper correctly if part of the paper is already covered with black. Read about that in this article: Epson 3800 error: Incorrect paper size or Paper error.
I’ve only used Epson printers, but those tips may also apply to other brands of inkjet printers.
A friend of mine was printing on an Epson Stylus Pro 3800, and as the paper tried to load the printer displayed an “Incorrect paper size” error even though the size of the photo paper matched the Paper Size selected in Page Setup. And it worked just a few minutes earlier.
My friend was trying to print multiple images on a sheet, in multiple passes. As a troubleshooting step, I turned the paper around and inserted it the other way. It worked. Why would the printer accept the paper size one way but not the other?
I came up with a theory about it. Unlike my older Epson, the 3800 can perform automatic nozzle checks and head alignments, and can sense paper sizes. I have read that it can do all this because of an optical sensor built into the printer. Now, my friend was printing images with large areas of black near the edge, and she was printing borderless. I believe that when she loaded paper that had a large black area extending about halfway across the paper, the optical sensor saw all that black and decided that the paper’s edge didn’t actually begin until the white area appeared.
I have also run into a similar problem where the Epson 3800 will simply say “Paper error” and tells you to press the paper feed button and try again. In this case I am feeding an edge that is partially printed along the leading edge, though not completely black and with a thin empty border along the edge. Even then, the 3800 senses a misfeed even though there’s nothing physically wrong with the sheet. Inserting a blank sheet loads successfully.
This behavior indicates that the optical sensor is designed to think of paper as a broad expanse of empty white, and it may incorrectly believe that long dark areas are not paper and indicate a paper feed misalignment. If you’ve previously experimented with multiple-pass printing on another Epson printer model, you may not be able to make it work on Epson printers that try to sense blank sheets optically.
Some reading on the Web indicates that certain Epson models are able to turn off this automatic page size sensing, but that feature doesn’t seem to be available on the 3800.