The detection was just added to Definition: 1.111.187.0 on Aug. 18, 2011.
MMPC Threat Encyclopedia-VirTool:Win32/Obfuscator.RP http://www.microsoft.com/security/portal/Threat/Encyclopedia/Entry.aspx?Name=VirTool%3aWin32%2fObfuscator.RP
This threat is detected by the Microsoft antivirus engine. Technical details are not currently available for this threat.
For general reference on the familyWin32/Obfuscator see http://www.microsoft.com/security/portal/Threat/Encyclopedia/Entry.aspx?Name=Win32/Obfuscator
Try updating MSE and performing a full scan or download the Microsoft Safety Scanner and run in Safe Mode.
Alternatively try Malwarebytes Antimalware or ESET Online Scanner if you can still access the internet through Internet Explorer.
Microsoft Safety Scanner
http://www.microsoft.com/security/scanner/en-us/default.aspx
How to use Malwarebytes' Anti-Malware to scan and remove malware from your computer
http://www.bleepingcomputer.com/virus-removal/how-to-use-malwarebytes-anti-malware-tutorial
ESET Online Scanner
http://www.eset.eu/eset-online-scanner
If you cannot access the internet using your computer try using another clean computer to download Microsoft Safety Scanner and/or Malwarebytes to aflash drive and then transfer to your infected machine.
Since you are using Microsoft Security Essentials you might consider contacting support.
start here - https://support.microsoftsecurityessentials.com/ and select the link that says - I think my computer is infected - and then select the support option for phone, chat or email (options will vary by Region).
If you are in North America, you can call 866-727-2338 for free help from Microsoft for virus and spyware infections. In other regions not served by the link above, go here: http://Support.microsoft.com/security and go to the "assisted support" in Contact menu.
Also, Microsoft now offers no-charge, online (third-party) support for such issues Virus & Malware removal with Microsoft Security Essentials
http://supportservices.microsoft.com/support/services/virus_essentials
Hope this helps.
Hello, everyone!
Today I've noticed that my computer is infected by VirTool:Win32/Obfuscator.RP
My Opera and Chrome browsers stopped working correctly.
I'm using Microsoft Security Essentials, but they can not kill the virus!
Which antivirus is able to do that?

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