COMPUTER VIRUSES

Currently you are more likely to infect your computer with a virus/worm by reading an infected e-mail message than by any other route. Mass mailings of virus/worm infected e-mail messages are leading to widespread infections. It is therefore very important that you adopt procedures for reading your e-mail that give the best possible protection from e-mail aware viruses. This document is intended to outline some of these procedures.

Some guidelines to preventing a system becoming infected through infected e-mail attachments:

• Always install anti-virus software and keep it up-to-date (this may mean downloading updates daily!).
• Learn how to use and update your anti-virus software.
• Never open an e-mail attachment without firstly scanning it for a viral infection.
• Do not configure your e-mail client to automatically open attachments. Save the attachment to disk into a folder designated to hold attachments prior to them being scanned for viruses then scan the folder.
• Do not open any attachments with a double file extension, (e.g. filename.TXT.pif), normally files are not given a double extension.
• Do not assume that because you recognise the address of the sender of the mail message that the message is uninfected, many e-mail aware viruses use the addressbook of the e-mail client to forward infected messages to addresses stored within the addressbook.
• Be suspicious of all messages purporting to be jokes, screen savers (such as the W32/Parrot e-mail worm), pictures, especially from unknown sources.
• Do not assume that because an attachment has a .bat or .pdf extension that it is incapable of carrying viral information, for example, the PeachyPDF-A worm makes use of .pdf extensions and W32/Magistr-B makes use of .bat extensions.
• Remember that many of these viruses/worms target well-known e-mail clients such as Microsoft Outlook. You should therefore keep your e-mail client software up-to-date and install any software patches issued by the software's producer.