Another message cautioned, opening any E-mail message called death ray will infect your computer with a deadly virus pass on this information to everyone you know.

Watch out, computer users. If you haven't been bitten by an E-mail virus yet, you will. At least that's what the writers of thousands of electronic mail messages warning of computer viruses that are spread by reading E-mail want you to think.

Just ask Tomas Schreiber-Ringel, a German computer user who opened up his electronic mail recently and was alarmed to learn that reading any E-mail message with the subject win a holiday would result in the corruption of vital files on his computer's hard drive. The message urged him to pass on the warning to others.

Does anybody know about this virus andits relevance to Windows NT? Schreiber-Ringel asked on an Internet chat area. The truth was, this virus warning, like hundreds of others, was a hoax.

But enough people are confused about the origin of computer viruses that the pranksters who create such messages are encouraged to continue.

So here are the facts: a computer virus cannot exist in an E-mail text message, nor can one be spread simply by reading an E-mail message. Viruses also cannot exist in usenet (newsgroup) postings or simply float around the Internet.

If you're ever the victim of an E-mail virus scare, remember that viruses must be attached to and infect an executable programme, says Andy Hagemaker, a system administrator for a telecommunications company in Virginia.

Viruses and other system-destroying bugs can only exist in files, and since E-mail is not a system file, viruses cannot exist there. While reading E-mail, you are not executing any malicious code.

It's unfortunate, says Robert Slade, author of the book Robert Slade'sGuide to Computer Viruses, that so much effort goes into taking precautions against things that aren't there.

But that doesn't mean that people should let down their guards entirely when it comes to computer viruses. Viruses are real, but unfortunately in this day and age, you need to be somewhat informed about what they are in order to avoid wasting time chasing phantoms.

Essentially, a computer virus is a programme that attaches itself to or substitutes itself for another programme. In addition, most viruses can replicate themselves. Typically, viruses spread via floppy disks, computer networks, modems, or other means. Some viruses are designed to destroy data, others merely want to play a prank on you, such as displaying a message on your screen like you're stoned at random intervals.

Be aware, though, that while no virus can be spread by reading the text of an E-mail message, viruses can indeed be distributed as attachments to E-mail messages.

Attachments are files -- such as a wordprocessing file or a programme's main executable file -- that ride along with an E-mail message. Most E-mail programmes today allow you to include attachments with your messages.

And because an attachment can be a virus-infected file and not merely text, it could cause damage to your system. Fortunately, a file attached to an E-mail message cannot download itself automatically to your hard drive. You must specifically take the proper steps to save the file attachment to your system.

That's why it's a good idea to run a virus checker in the background whenever you use your computer and to keep the virus checker's so-called signature file -- its record of existing viruses -- up-to-date. That way, if you unattache a virus-infected file linked to an e-mail message, your virus checker should alert you to the problem.

So how can you spot an E-mail virus hoax? First, look for bad writing style, says Bruce P. Burrell, member of the University of Michigan's antivirus team. Lots of exclamation points, allcapital letters, and misspellings -- those are definite tip-offs.

Also, says Eric Gerlitz, author of a World Wide Web page on the subject, if you carefully read these hoax letters, you can pick out strange, nonsensical technical jargon used to confuse and scare those who aren't computer experts.

Gerlitz says this jargon usually concerns systems of a computer that don't even exist or things that aren't possible. One recent e-mail virus hoax called bad times, a parody of the good times scam, warns of a computer virus that will wreak havoc throughout your home, demagnetising credit cards, scratching audio CDs, and re-calibrating your refrigerator.

(DPA)Keep in mind, too, that viruses are almost always specific to particular operating systems. So if you get an e-mail message one day that warns of a virus and does not specify the operating system on which it runs, chances are good that you can safely discard it as a hoax.