My bet is there is some downloader app, virus or trojan. Those "downloaders" are often problematic so try scanning with Grif's ideas at the next link.
http://forums.cnet.com/7726-6132_102-5098912.html?tag=posts;msg5099421
Bob
Says detected a virus when I know that the downloadis clean. I tried tlowering security settings and taking off AVG but still ays that and won' even lt me load AVG again

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