http://support.microsoft.com/default.aspx?scid=kb;en-us;315688
http://support.microsoft.com/default.aspx?scid=kb;en-us;316505&FR=1&PA=1&SD=HSCH
http://support.microsoft.com/default.aspx?scid=http://support.microsoft.com:80/support/kb/articles/q314/8/78.asp&NoWebContent=1
Hard disk problems in the link above from microsoft...dunno if it will point you in the right direction.
Are you 100% sure you aren't having temp files fill up your diskspace and then they purge if you log out? Just wondering...I'd try optimizing my hard disk a bit.
1. Delete all offline files
2. Delete all temp files
3. Empty recycle bin
4. Disable system restore and see if it makes a diff. and if not re-enable
5. Check for LARGE files in your windows/system32/logfiles directory...look specifically for 'trace logs'
6. Defrag and scandisk
Also...if trace logs are causing problems (form #5 above) try Control Panel, Administrative Tools, Performance
Open 'Performance logs and Alerts'
Open 'Trace logs'
right-click the log file(s) and change their Properties. You can change their schedule, and whether they are active or inactive.
right-click the log file(s) and delete.
I'm not sure if all of this is even relevant because from the sounds of it, you have a relatively uncluttered drive and this only happens when you open photoshop. Does it occur when you open other programs at all? If not, I'd be willing to bet you should probably uninstall photoshop and then reinstall it later. Let us know if there is anything else we can do for you and keep us posted on what happens :D
