I've noticed something very annoying about Illustrator. I have been working on a poster for the last week and EVERY time I restart Illustrator it NEVER has the poster as one of my RECENT items?????
Is there a reason why Illustrator can;t seem to remember that I was JUST WORKING ON THIS??
Two possible options:
a) You do not have sufficient security permissions to write your prefs or to the system registry (on Windows) when the program is exited.
b) The program actually never exits properly and quietly crashes. Under the hood, though, this is also a permission problem in most cases.
So, the most proper thing you can do is verify your user account settings or create a new user account with sufficient privileges to incvestigate.