You didn't tell. But look up XP SAFE MODE on google if you don't know how and try safe mode to log in as the administrator and while there create a new account just in case and then reboot, login as that new account and tell what happens.
Bob
My System is XP. Yesterday my sectary somehow got the a virus, in using a software we got online it found the virus (antivirus 360) and after the(Super Anti Spyware ) found the virus and said the computer had to reboot to complete the operation, it will not boot up.
First screen said to start in normal node, but the next screen says that system is in power saver mode, goes to the screen that says gateway, then back to the screen that says that your computer has shut down.

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