Illustrator error: Can't open the illustration

Typically it's either 1.  Permissions problem locally on the machine.  or 2.  The file is corrupt/damaged.  If it's corrupt or damaged you can usually open it...  Try right clicking and opening as administrator.
add as a new file and re save it.

http://kb2.adobe.com/cps/500/cpsid_50032.html

could not get my files to open (or place) into another Illustrator file, so I used another CS Program.
Here are the steps I took to get my files back:
* Open the AI file up in Acrobat.
* Do a "save as", and chose to the format "Encapsulated PostScript file" (EPS).
* Open the new EPS file in Illustrator. You will have to ungroup everything, as it groups it all in the Acrobat save.
* Problem solved. Hope this helps any future problems!

It shouldn't be a permissions issue, because the folders I'm opening these files from are all subfolders on a network drive that are inheriting from the top, and this user is one of the main group that has full control. Locally, this user is an admin also, because of some user account shuffling I did.
But I'll recheck the permissions on all folders involved so far.

I'll try the file resave, also; then I think I'll try a variation on it of saving the file as a new copy from my other Illustrator; and seeing if the problem program opens the fresh version.

I'll see about the folder after that.

Then let y'all know.

The local permissions relate to the Adobe folders. If the user is not listed in such he will get odd result when opening Adobe applications....

If you added the user afterwards it may be a reason.

Check the permissions on the All Users App Data folders and obviously the Users' folder. Also check the program Files folder permissions on the Adobe and Common Files folders
capt

It's definitely not a permissions issue. That user can save files to and delete from the specific folder where the problem was noticed.
But, more interesting info: Illustrator won't even save a brand new file anywhere  local scratch drive; the network drive; none at all.
"An unknown error occurred" apparently. Tried saving with compression off, PDF compatibility off, etc. No go.

I'm wondering if the administrative "trick" I was trying out for renaming domain user accounts without having to transfer all user data perhaps doesn't sit so well with Illustrator.
I've got another to test that on, and... nope, wouldn't appear to inherently be that account creation/transfer method, because Illustrator on the other computer I did that on has no problems.

Corrupt program files then? I found the Settings folder mentioned above, and ... that did the trick! After testing, it was specifically the AIPrefs file in that folder.
Well, perhaps there's my InDesign prefs equivalent.

Thank you for all your help!

Interesting. I wonder if it could be related to permissions making the AIPrefs not work correctly, because there was slightly funky permissions happening; but the user, in the end, was a local administrator.
So, it could be something related to that, but recreating the Settings folder led to the immediate resolution.
I'll see if other problems crop up in the future, and for now thanks again.