How to Stop Sobig.F
Tips and links to help you stop the Sobig variant from infecting your PC.
The Sobig.F worm is a variant of June's Sobig.A worm. The worm is also known as I-Worm.Sobig.f, W32/Sobig.F-mm, W32/Sobig.f@MM, and WORM_SOBIG.F.

Sobig.F only affects Windows systems, and it has been spreading rapidly since earlier this week. Machines running Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, and Windows XP are all susceptible to the worm.

On an infected system, the worm scans various documents for email addresses. The worm then distributes itself to other inboxes using a built-in SMTP engine. When it distributes itself, it "spoofs" in the "From:" field an email address it finds on the infected machine instead of using the infected user's address. Because the address doesn't match that of the infected machine, it's difficult to trace the string of infected computers.

The worm also has a built-in shutoff date. It'll stop working on September 10, 2003.

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