I am unable to get into my Windows OS. The computer sits at the user login screen with only the Windows XP logo showing. No user profiles are available. I have tried rebooting into safe mode and last known good configuration. I have alos tried booting from my restore CD and a Windows XP Professional Upgrade CD. All options end in the same, unable to get into windows. This means I can't get to a command prompt to run chkdsk or other utilities. It means I can't check for corrupt files. It means I can't do ANYTHING!!! Please help.