In event viewer you only want to look at a listing if it is an error, if it is just info do not worry
an error will be red with an x in it
a warning will be a yellow triangle with an exclamation point in it.
if you double click on the entry a dialog box will open with further info
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First, I am not sure if AVG is still supporting xp
see
HERE
also avg is not considered one of the top antivirus even when xp was still supported, that said
I want you to download the following and run them, you can uninstall them later if you choose:
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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when the scans are clean, NOTE: you may have to run each twice) and the issue is still occurring, then next I want you to create a new administrative account and then log into it and does the issue occur in the new account??