The latest virus attack is spreading via e-mail in the form of fake invites to join Twitter or Facebook. These invites look real enough but have a few key clues: 1) real invites will not have a zip file attached, 2) real invites will always list who is inviting you, and 3) hover over (but don’t click) the links in the message and make sure they really go to twitter.com or facebook.com and not for example twitter.com.ru or similar.
If you open the attachment or follow the links in the e-mail, your system becomes infected with a virus similar to the “fake UPS” virus. You will begin seeing pop-ups saying you need to buy an anti-virus or anti-spyware product to clean your “infected” computer. You may also see your system slow down dramatically and your e-mail become unusable.
If you get one of these fake invites via e-mail, you should delete the message. Do not open the attachment. Do not reply to the e-mail or forward it to anyone.