The Microsoft Office Help window’s title bar can sometimes get stuck under the menu bar. When that happens, you can’t move the Help window, and you can’t close it because the close button is part of the title bar. Because the Help window is more like a palette than a window, it doesn’t respond to any Close Window keyboard shortcut or the arrangement commands under the Window menu, and it floats above all other windows. It basically blocks your document window until you restart the application.

Short answer

Throw out the file com.microsoft.Office.prefs.plist, or if you want to be more precise, instead of throwing out that file, open it and increase the value for Help/Help_Top so that it clears the menu bar.

Long answer

Or, how I figured this out:

The usual suggestion for a problem like this is to delete an application’s Preferences file. I didn’t want to throw out the Preferences file because I’ve heavily customized my Office installation (toolbars, etc.) and I didn’t want to reconfigure everything from scratch. Mostly because I can’t even remember everything I’ve customized and now rely on (can you?). I suspected that there must be a setting in a preferences file somewhere that controls the position of the Help window, and if I could change that one thing I wouldn’t have to throw out the baby with the bathwater. And so I went looking for that setting.

First I tried AppleScript. I used the Script Editor to open the AppleScript dictionary for Excel, where I was having the problem, but I couldn’t find any commands that controlled the Help window.

I then started looking in the Preferences folder, in my Home/Library folder. You can read these files in TextEdit, but it’s nicer to use the free utility Pref Setter, which lets you view and edit the contents of a preferences file in a clean, easy, point-and-click way. I guess you could also use your favorite XML utility.

Now to find that window preference:

I looked in the file com.microsoft.excel.plist, but found nothing that looked right. While many Microsoft and Adobe applications have a preference (.plist) file at the top level of the Preferences folder, it turns out that these usually contain only information for the Open and Save dialog boxes. The real preferences files are usually buried deeper. But how was I going to find it? I typed “excel” into the Find field in Pref Setter’s Open Domain Quickly window, and it revealed a list of files inside the Preferences folder with Excel in the title.

Unfortunately, I still didn’t find what I was looking for. I thought to myself, maybe it isn’t specific to Excel…if it’s about the Help file, could it be an Office-wide preference? To test that, I typed “microsoft” into Pref Setter’s Find field and it turned up many more files, including some in a Microsoft sub-folder.

I opened com.microsoft.Office.prefs.plist. It’s a long list of preferences, and I wasn’t sure I could find the one I wanted. But there’s a Find field in the com.microsoft.Office.prefs.plist window, so I typed “help” into it to try and narrow down the list.

Aha! That revealed several preference settings:
Assistant\AsstWithHelp
Help\Help_Bottom
Help\Help_Left
Help\Help_LeftPaneWidth
Help\Help_Right
Help\Help_Top
Help\Help_ZoomedOut

Bingo.

Help\Help_Top was set to 22. I was pretty sure that was a vertical offset from the top of the screen, and guessed that if I set that to a much higher number, the window would move down. I changed the number to 100, saved the document, started Excel, and opened Excel Help.

Fixed!!!

I hope this serves as an example of how to locate application preference settings with the help of a utility like Pref Setter.