Hi. My name isXXXXX you for your question and the opportunity to assist.
Please try the following steps to perform a System Restore to return your profile to the state it was in when you were able to log in normally. This will not affect your data files.
Start or restart your machine. As soon as you see the HP logo begin tapping the F8 key to get to the black screen with your startup options. Using the up/down arrows select Safe Mode with Command Prompt and press Enter. When you get to the prompt (C:\Windows\System32>_ ) type: rstrui.exe and press Enter
This will launch System Restore.
Note: It can take a minute or two for the System Restore window to open so please give it some time to come up.
When the window opens Vista will recommend a restore date,
click on the Choose A Different Restore Point option and select a date when you know you were able to log in successfully. Follow the prompts to finish the restore. Your computer will restart and you should then be able to log in normally.
Important Note: Sometimes the first restore point will not work. If that is the case, repeat the procedure and work your way back through the restore points choosing an older one each time.
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