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Works great - many thanks. Is there a way of scheduling the full system scan as opposed to the quick scan, though?
You can scan every file on your system with that you just have to indicate what drives you want to scan in the scheduled task as indicated in the link Eddy gave you.
"C:\Program Files\Alwil Software\Avast4\ashQuick.exe" C: E: - this will scan the entire contents of the C: and E: drives
However, the major disadvantage with the task scheduler trick of using ashquick.exe is, it will scan every file of the hdd, partition, folder or file that you set it to scan; even those files not considered a potential threat, this can take a long time.
The Pro version gives a lot more flexibility and the scan would follow the settings and exclusions, etc. of the regular scan.
I prefer to do a manual scan with my regular weekly maintenance tasks.