Please note that the virus alert which was reported by ktlawson is a hoax - not your fault ktlawson.
Key "invitation virus" into google and you will see lots of hoax references.
I have looked on McAfee's site and there is no mention of it .. Well there was in 2000 and it has what looks like the same words as in ktl's post.
http://us.mcafee.com/virusInfo/default.asp?id=description&virus_k=98893 (http://us.mcafee.com/virusInfo/default.asp?id=description&virus_k=98893)
Nor is there anything on CNN's web site or Microsoft's.