I have a friend who is using QB 2008 Pro under Windows 2000 on a peer to peer network. QB is on her machine and her machine only. It is not in multi-user mode and she is the only person authorized to use it (she's the owner of the company, a small company of 6-8 employees including herself).
Several times since she switched to 2008, when she saves or backs-up QB, she gets an error message the indicates that the data base files cannot be found and that the program should be running on the same machine she is using. IT IS! The error number is different each time and since the machine is essentially locked up, she cannot access cut and paste or the Intuit tech support number to tell them the problem.
She just called me after losing 2 hours of work. She's not a bookkeeper by training but is more than a little savvy about computers. She'd be posting this but she's busy re-entering that 2 hours worth of work.
After re-booting everything appears to be working. Next time I told her to write the error number down and have the tech number handy before hand or call me to get the tech line. She was practically in tears when she called. She needs to be running her business, not calling tech support.