Note: If you're asking for technical help, please be sure to include all your system info, including operating system, model number, and any other specifics related to the problem....
What is your OS,is it XP pro?
Have you run any scans?
Did you try last known good config?
I have a gateway 450 rog laptop that likes to lockup at the login screen, it will say windows is loading but not give any login accounts to activate so you can get windows to load up. If you tap the enter button at just the right time you can get past this and to the account log in, but if you miss it or it doesn't make it that far on it's own, you have to do a hard shutdown and try again. Any ideas people. By the way there is only one logon account active.