You can use a program like Revo Uninstaller, but you have to be careful to check all the registry entries to be sure they refer to just the program you are uninstalling.
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what I like to do is use find in regedit and delete the entries myself. and I do a search through my pc with all hidden files unhidded for the program also. Lots of programs leave remnants, and some leave a driver behind, you would go to device driver and look at the hidden drivers to see these.
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when you say no success on restore, do you mean you could not run a system restore or that when you restored the problem did not go away???
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run the following to insure that you are clean:
make sure you get the free one and check each page before clicking next to insure that you do not install any added software:
Download, install, update and do full scan with these free malware detection programs:
Malwarebytes Free (MBAM):
http://www.malwarebytes.org/products/
SUPERAntiSpyware: (SAS):
http://www.superantispyware.com/
Remove all found, reboot, and run again until scans run clean, these can be removed afterwards if you so choose. Run scans one at a time, please.
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you might want to check with AVG to see if it is still supporting xp, I personally would not use AVG, but it is up to you.
I know that 360 Internet security by Qihoo is still supporting xp.
post back with results of cleaning.
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in autoruns look for any program that you do not know what it is, and if you still cannot paste here then type the entry in so I can check it for you.
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You can also look in event viewer to see if there are any errors about this issue.