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I have a home computer with Windows 7 64-bit Pro installed. For nearly all of what I do, this setup works great, but I have some web applications which won't work. I've experimented and discovered they work fine on a Windows XP 32-bit virtual machine (with IE 7).
I use this virtual machine very infrequently and only for web applications. I would have no problem wiping it and creating a new one if necessary, so the question is whether I need to install antivirus software on it. Is it possible for viruses to propagate from the virtual machine to the host?