To all of Sumner County Message Board participants: The following was published tonight (May 30) in our Huntsville Times from the Knight Ridder News Service. Please read! A hoax suggesting that people should delete a crucial Windows file is making the rounds on the Internet this week. The e-mail claims that unless people delete the program in question, a virus will attack their system on Friday. "It was brought to my attention yesterday that a virus is in circulation via e-mail." The text of the message reads. "I looked for it and to my surprise I found it on mine. . . Please follow the directions and remove it from yours TODAY!!!!" The message goes on to tell readers that the file SULFNBK.EXE travels via e-mail and slips itself into the C:/Windows/Command folder, where it lies in wait until Friday. On that date, the message says, the file will activate and wipe out all files and folders. The only problem: SULFNBK.EXE is a crucial Windows system file, present on every computer running a copy of Windows. It helps Windows recreate long file names if they get corrupted. The virus hoax is sweeping the Net, as concerned friends send it to one another at the speed of e-mail. The SULFNBK.EXE filename was the top gainer among terms that people searched for on the Google Web search site during the weeks of May 15-21 and May 22-28, spokesman David Krane said. Confusingly, there is a virus that can possibly use the SULFNBK.EXE filename, though it doesn't always. Going by the catch name W32.Magistr.24876@mm, the virus can infect that file, among others, on your hard drive. But you must receive it separately via e-mail, and it probably won't live in the C:/Windows/Command folder. Symantec's AntiVirus Research Center, www.symantec.com/avcenter, advises that you should not delete SULFNBK if it resides in the correct folder on your hard drive. Make sure you have anti-virus software running and that you've updated that virus definitions since mid-March when the W3.Magistr.24876@mm virus was discovered. If you've already deleted the innocent file, you can get it back. Check with your computer manufacturer if you're using the version of Windows your machine came with, or with Microsoft if you've upgraded since you bought your PC for instruction on how to get it from your Windows CD.