— especially if the message tells you to!
It is very likely that you will get e-mail warnings about a huge, horrible virus that will “burn your whole hard drive” or some such horse-hockey. These hoaxes probably go around more during the Christmas season because people are actually sending e-cards. This makes a warning about e-cards more potent.
The facts are: Viruses and worms may attack your computer if you click on links in e-mail from unknown senders. One disguise for bad e-mail is a greeting card notification. BUT there is no big new terror lurking out there. Reasonable precautions — updated and fully functioning antivirus, Windows security updates regularly installed — and common sense are all you need to be perfectly safe.
Don’t click on links in e-mail! That is a simple rule that everyone should learn in Internet Kindergarten.
The other rule is, don’t forward e-mail! If you must send something on, copy and paste (more kindergarten) the old message into a new one.
But before you tell all your friends about the latest impending doom, check it out for yourself. Use whatever search engine you like, but use it. You will usually find out that the same tired old e-mail has been going around for years.
Don’t send lies onward. Find out the truth and send it back.