My laptop has a virus. Any ideas on how to get rid of it? It's coming from an anti-virus program that's popping up and wants me to purchase it. When I click on my existing Avira(?) program it wont run and I get a message saying the file is infected and wont execute, do I want to run an antivirus program. If I click 'yes', the popup for the AntiVirus comes up and wants me to buy it. If I click 'no' nothing happens. Same message when I try to do a Windows system restore.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13