This is the latest in a series of monthly charts counting down the ten most frequently occurring viruses as compiled by Sophos, a world leader in corporate anti-virus protection. For February 2002, the chart is as follows, with the most frequently occurring virus at number one: 1. W32/MyParty-A (My Party) 18.9% 2. W32/Badtrans-B (Badtrans variant) 15.7% 3. W32/Klez-E (Klez variant) 13.5% 4. W32/Klez-G (Klez variant) 10.0% 5. W32/Magistr-B (Magistr variant) 4.8% 6. W32/Sircam-A (Sircam) 4.5% 7. W32/Magistr-A (Magistr) 3.2% 8. W32/Nimda-A (Nimda) 1.8% 9. W32/Hybris-B (Hybris) 1.5% 10. W32/ElKern-B (ElKern variant) 1.4% Others: 24.7% "The MyParty worm duped computer users by pretending to be a link to a website containing snaps of groovy partygoers. But not everything that ends in dot com is a web address, it can also be an executable file," said Graham Cluley, senior technology consultant for Sophos Anti-Virus. "It was a simple psychological trick and many people fell for it. The message is simple: stop double-clicking on unsolicited email attachments, even if they appear to come from someone you know." February also saw the emergence of Coolnow - a worm that infected users of MSN Messenger. Although it did not break into the top ten, Coolnow continues to infect PCs and therefore offers a reminder that virus writers are constantly using new platforms to spread their malicious code. 739 new viruses were discovered and protected against by Sophos Anti-Virus during February 2002. The total number of viruses Sophos now detects and protects against is 72,569.