There is a new virus out that masquerades as several official-looking emails or files. It pretends to be from WinZip, Yahoo, Microsoft, and several other places - please be very very careful whenever opening any attachment in an email, or even when clicking on links in emails. Just clicking on a link can either run a virus or send you to an infected website where your browser will run the virus automatically. You can also get infected simply by opening an email in Outlook or using the Preview Pane to see the email contents without opening it.
W32/Oror.b@MM is detailed at http://vil.mcafee.com/dispVirus.asp?virus_k=99786
W32/Oror.e@MM is detailed at http://vil.mcafee.com/dispVirus.asp?virus_k=99787