vBulletin Embedded with a Virus?

[meissenation]

I'm getting reports that most of my users are getting virus alerts when they visit the site. Unfortunately, I don't have this issue on my own computer so I can't speak first hand what's going on, just what they tell me. I'm going to a friend's house tomorrow to see what happens on her computer first hand. I don't know if the security has been compromised or what. There's nothing malicious done to the admin section, I can login perfectly fine and all that. When they visit the site, don't even have to be logged in, they get anti-virus warnings that a threat has been identified in the temp files and they have to delete/disinfect the files before they can even fully view the website. This only happens on my site, they said they never experience that problem when they try to view any other site. Now a few of the guys are reporting that they can't view the site at all, it just sits there trying to load but nothing ever opens... just the bottom status bar for the browser shows like "one or two bars" but it never loads. I had one of them try pinging the site's IP address, and they can ping it fine, it just won't load -- I'm guessing this is related to the security threat that their antivirus warns them of. Does anyone have any ideas? This board isn't modded that much, here's a list of the installed products:

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