What Is a Clean Boot for Windows for Workgroups?
http://support.microsoft.com/support/kb/articles/Q90/5/11.asp Then edit your win.ini file and remove or comment out (;) any Load= or Run= lines. Finally, start Windows from the DOS prompt and hold down the Shift key during startup to disable loading any programs in the Windows Startup group. This should result in a clean boot. See if you still have the problem at this point. You can also create a log file at boot by invoking Windows with the win /b command.