Thank you for your reply too, Jacob. I changed the AI Prefs file and enabled content recovery. I then tried to open the file by starting up Illustrator, going to File>Open>path to file> Select file> Ctrl + Shift + Alt click Open. It still would not open the file, it said the same thing about being an unknown format.
In the Prefs file I have this now:
I saved the file, but took the extension out.
I was not able to do Step 2 from this link: http://kb2.adobe.com/cps/500/cpsid_50032.html
I do not see a recovered file.
I opened the AI Prefs file in NotePad then I saved it at the Windows XP: C:\Documents and Settings\<user name>\Application Data\Adobe\Adobe Illustrator [version] Settings\en_US\AIPrefs path as a txt file. I then went to this path in Windows Explorer & deleted the .txt extension. The file looks like this "AIPrefs"
without an extension.
I just tried opening the file into Acrobat, but it said Acrobat could not open because it is either not a supported file type or the file has been damaged.
Here is what I did...
I found this link: http://en.allexperts.com/q/Adobe-Illustrator-1027/open-ai-file.htm
I placed the .ai file into InDesign then exported it as an .eps file. It now opens in Illustrator. There are no text boxes, just those blue lines (I don't remember what that is called), but I can edit text.
I saved as a .ai file and it opens.