Another new variant of MyDoom worm - Mydoom.T, was found on September 3rd, 2004. This worm variant is similar to previous ones. It spreads in e-mails with different subject and body texts, to Kazaa P2P (peer-to-peer) file sharing network and also drops a backdoor component that listens on port 5422. Additionally the worm can perform a DDoS (Distributed Denial of Service) attack against Microsoft's website.
Depending on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the suspect file, or ask you for a desired action.
More information on the scanning and removal options available in your F-Secure product can be found in the Help Center.
You may also refer to the Knowledge Base on the F-Secure Community site for more information.