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Is the file %SysDir%\avisar.exe located on your computer? Your computer is infected.
We highly recommend you to remove %SysDir%\avisar.exe from your computer as soon as possible.
%SysDir%\avisar.exe is Trojan/Backdoor.
Kill the process %SysDir%\avisar.exe and remove %SysDir%\avisar.exe from Windows startup.