Anytime I double-click on an Illustrator file to open it, the Illustrator CS6 window opens up too small to view the file. It comes up with an error message that says "Can't open the illustration. There is not enough room for the window; increase document area and try again."
If I then click on the box to expand the Illustrator window to full-size, then I can open the file. It's just frustrating that everytime I try to open an AI file by double-clicking on it, I get this error message.
I am having the same problem, also Windows 7, and this solution did not fix the problem. I've had this version for three months now and it only just started doing this. Unfortunately I didn't note when it started to check if it had to do with an update or something.
This bug causes the most hassle with email attachments that are not saved anywhere yet. However, when I go File > Open Recent Files, the file is listed, even with email attachments. When I double click on the file from there it opens.
A little late to the party, but I've found this error only happens if the Illustrator window is maximized. If your window is not maximized, you should be able to double-click an .ai file and won't get the error. Still, it's a bug that should be addressed.
I am also having this problem in Windows 7. I tried the fix (unchecking "open in tabs"), but that did not work. Anytime I try to open Illustrator CS6, it opens in a tiny window. Really annoying to have to max it every single time I open it. This is whether or not I click on a file to open it or click on my desktop shortcut to open it. Surely after a year, Adobe has released a fix to this problem. Anybody know where I can find it?
I'm also getting constant messages when I save saying Illustrator is not responding. Over and over... I know this isn't the spot for that, but my CS6 seems to be very buggy.