Virus Warning: W32.Nimda
You may already know that new viruses appear all the time and that as a general principle you should regularly update your virus protection.
From time to time new viruses appear which spread very fast and cause a lot of damage. Melissa, LoveLetter and CodeRed are examples.
The latest virus rampaging around the internet is called W32.Nimda.A@mm. If you want technical details you can see them at http://vil.nai.com/vil/content/v_99209.htm. It can infect systems indirectly using a variety of means but for most users it will appear in email. Under certain circumstances you can catch it if you browse a web page hosted by an infected web server.
Most anti-virus vendors have included this in their virus updates so you should update as soon as possible. Even if you updated recently, you should update again.
If using Symantec, use LiveUpdate or go to http://www.symantec.com/avcenter/download/pages/US-N95.html.
If using McAfee, see Cadzow Knowledgebase Article 1355.
If using Vet, use AutoDownload or go to http://www.vet.com.au/servlet/displaydisks/areas/ALL/UPDATE.
Some (not all) of the virus' effects are mitigated by applying system updates. If you are using Microsoft Internet Explorer, you should have 5.5 or better, if you are using Windows NT you should have Service Pack 6 and the Security Rollup Patch (SRP) and if you are using Windows 2000 you should have Service Pack 2. This type of virus again highlights the need to keep your operating system, applications and virus protection up to date. Virus protection alone sometimes is not good enough.