Your AVG Antivirus might be desabled or damaged....
It might desabled due to new antivirus installation or from another reason
to enable that click start button -->run
write msconfig
click on ok
system configuration utility will open then goto
startup and check AVG(grisoft services) and also goto services and check on hide all microsoft services
and then check grisoft services
IF PROBLEM OCCURED AFTER RESTARTING THEN ITS SURE THAT YOUR AVG INSTALLATION IS DAMAGED AND PLEASE REINSTALL IT....
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CHECK IT OUT
