Any of you who have recently downloaded Classic Shell need to be aware that some of their download sites were compromised, and the original files replaced with a malicious version that overwrites the MBR and possibly more.

There is a complete thread about it here.

 

http://www.classicshell.net/forum/viewtopic.php?f=12&t=6434

 

It is recoverable:
 

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Hey all, to those affected by the malware, I just fixed my partition table on my compromised drive using this software:

http://www.cgsecurity.org/wiki/TestDisk

Restored my partition table completely with no issues. Did a quick scan and then added the found partition back and wrote it to disk. You will definitely want to rewrite the hard drive's MBR code with the Windows MBR code though. 

http://www.thewindowsclub.com/repair-ma ... br-windows

Damn! That was close. I just added Classic Shell to a new WIN10 install on a machine I put together last week. But, fortunately, I got it from ClassicShell.net/downloads.