Have you tried running windows in safe mode and doing a system restore from that point
Last night my daughter's Win XP PC was fully functional and this am it boots up but email, and most programs, including antivirus and antispyware utilities will not open.
For some reason Norton and SpySweeper wll not open and both tell me to reactivate in order to use.
Yahoo Messenger still works as does Microsoft Messenger.
I have tried the F8 procedure during bootup and have selected both return to last operation windows and restart in normal mode but nothing I have done seems to get me back to a working condition.
System Restore does not work either. I ran MicroTrends virus scan and nothing was found.
Does anyone have any ideas or suggestions on what has happened?