July 26 (Bloomberg) -- A variant of the Mydoom computer virus that infected 300,000 computers in February is spreading rapidly through e-mail, said researchers at Symantec Corp., the largest maker of anti-virus software.

Symantec has seen 250 samples of e-mails that carry Mydoom.M, more than other recent viruses, said Oliver Friedrichs, a senior manager with Symantec Security Response in Redwood City, California. The e-mail arrives disguised as an error message that says the computer user's e-mail can't be delivered. It urges him or her to open an attachment, which then propagates the infection to other users.

To contact the reporter on this story: Tiernan Ray in New York at tray2@bloomberg.net

Last Updated: July 26, 2004 13:21 EDT