Hi Marie,
Welcome to Microsoft Answers!
I would suggest you to turn off Windows Update and then run a Malware scan on the computer.
a.Open Windows Update by clicking the Start button, clicking All Programs, and then clicking Windows Update.
b.In the left pane, click Change settings.
c.Choose the option Never Check for Updates and click on Ok.
If you get the consent prompt to click on continue, click it.
Check out the link below which talk about How to turn automatic updating on or off
http://windows.microsoft.com/en-US/windows-vista/Turn-automatic-updating-on-or-off
Now restart the computer and check if the issue repeats.
Download the Malicious Software Removal Tool from the link below and scan for Malwares.
Note: Windows Update Status should be off while running the Malware Scan.
http://www.microsoft.com/security/malwareremove/default.aspx
Once you run the Malware Scan, then try Turning on Windows Update and check if the issue repeats.
Hope this information is helpful.
Regards,
Mouneshwar R – Microsoft Support
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