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An hour to download? I hope you mean it takes that long to download SP2?
What Bob meant was for you to download the avast uninstaller, run it to remove the bad install of avast that you have now, and then re-install avast BEFORE downloading SP2. That way, you will be protected while doing the long download.
It should only take a few mins at most to re-download the avast installer. So, you should be fairly safe doing this. Once you have the new copy of the installer, you can then dis-connect from the internet. Be sure to stop all possible programs running before re-installing avast!
But, I see your point. If it scans C drive then it should scan F drive ... unless, you have somehow protected F drive from this?
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