W32/Mydoom@MM spreads through e-mail. This worm can disguise the sender's address, a tactic known as spoofing, and may generate e-mails that appear to have been sent by Microsoft. Many of the addresses Mydoom uses are valid addresses that are being spoofed for malicious purposes.

Mydoom Virus Alert: What to Do
Treat all e-mail attachments with caution, particularly .zip files in the case of this virus, even if they appear to be from a trusted source.

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