sulfnbk. Virus or hoax?
 

I received a warning about a virus which is supposed to remain dormant for 14 days.

The warning instructs me to search my hard drive for a file named 'sulfnbk' and delete it.

Now. Am I being paranoid or is this a hoax designed to make you delete an important file?

This hoax is not new but there has been a major second wave in the last few days.

There are three separate issues.
1) The real sulfnbk.exe file that is used by Windows is located in the C:\Windows\Command folder. Don't delete it.
2) The virus/worm W32.Magistr.24876@mm often is delivered as an attachment named sulfnbk.exe. If this file arrives as an attachment to an email message, then the file is undoubtedly infected. Do not run it. Dispose of it - there is no reason for anyone to send such a file.
3) Then there is the (clever) sulfnbk.exe email hoax. It is sent by someone you know (who doesn't know he is sending it). It says that he has been alerted to malware called sulfnbk.exe that McAfee and Norton cannot find. He states that he found this "virus" file on his PC even though virus checkers overlooked it and that it must be disposed. Ha! If Norton or McAfee does not find a virus in your sulfnbk.exe that is because there is none. Don't discard the file, disregard the hoax.

Yeah, I got the second version.

No harm done though.

Wouldn't mind getting my hands on the t0ssers who send these things.

sulfnbk.exe is an important system file but not "Mission Critical". So Windows will run without it until you, or the system, calls for a backup of a file with a long file name (ie with a name >8.3 as in DOS).

sulfnbk simply stands for "Set Up Long File Name Back up".

If you have deleted it, you can restore it from your Windows disk either compressed as sulfnbk.ex_ or in one of the Cab files. (Not sure which.)