The fake warning tells users to search their hard drives for a file called JDBGMGR.EXE. The message also advises users to delete the file because it is infected by a virus which may trigger after 14 days.
But JDBGMGR.EXE is the Microsoft Debugger Registrar for Java and may be present quite legitimately on many computers.
The confusion is compounded by the W32/Magistr-A virus which is capable of emailing infected copies of JDBGMGR.EXE to innocent users. Most anti-virus software has been capable of detecting W32/Magistr-A for over a year.
"If you receive an unsolicited executable file in your email, simply delete the email," said Graham Cluley, senior technology consultant at Sophos Anti-Virus. "This is a confusing hoax, but the message is simple: you should never launch or open unsolicited code on you computer. The best way to check for a virus infection is with anti-virus software. If your anti-virus software is up to date, you will be protected from the Magistr virus anyway."
Sophos reminds users that they should not pass on virus warnings to friends. Instead, check the facts at an anti-virus website, or forward the warning to the person in your company who is responsible for virus protection so they can decide if it is valid.
Sophos offers a free hoax information feed, which enables webmasters to place "always fresh" data about the latest internet myths, as well as real virus threats, on their public websites and company intranets. For more information, and to quickly add the feature to your website or intranet please visit: http://www.sophos.com/virusinfo/infofeed/
Sophos has published advice on this hoax at:
More information about Magistr-A is available at:
Sophos is one of the world's largest specialist developers of anti-virus software. Headquartered in the UK, its products are sold and supported through a global network of subsidiaries and partners in more than 150 countries. Sophos solutions are specifically designed to protect businesses and organisations from virus attack. The company's products are widely deployed by large corporations, banks and governments.
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