To remove this completely it is best to combine MBAM and SAS.
MBAM, Trojans will block the downloading and installation of MBAM. If this happens, download it from a known clean computer, update, and rename the executable file before executing on the infected computer.
So do a separate scan of another security program so that other infected files not detected by anti-virus application can be remove as well. Download and run SuperAntiSpyware Portable Scanner. Download and Instructions to be found here: http://www.superantispyware.com/portablescanner.html

Manual removal instruction to check on afterwards:

Remove associated files:
%UserProfile%\Local Settings\Application Data\opRSK
%UserProfile%\Local Settings\Application Data\pw.exe
%UserProfile%\Local Settings\Application Data\MSASCui.exe
%UserProfile%\AppData\Local\opRSK
%UserProfile%\AppData\Local\pw.exe
%UserProfile%\AppData\Local\MSASCui.exe Not
Remove registry entries:
HKEY_CURRENT_USER\Software\Classes\pezfile
HKEY_CLASSES_ROOT\pezfile
HKEY_CURRENT_USER\Software\Classes.exe\shell\open\command “(Default)” = "%UserProfile%\Local Settings\Application Data\pw.exe” /START “%1″ %*
HKEY_CURRENT_USER\Software\Classes\pezfile\shell\open\command “(Default)” = "%UserProfile%\Local Settings\Application Data\pw.exe” /START “%1″ %*
HKEY_CLASSES_ROOT.exe\shell\open\command “(Default)” = "%UserProfile%\Local Settings\Application Data\pw.exe” /START “%1″ %*
HKEY_CLASSES_ROOT\pezfile\shell\open\command “(Default)” = "%UserProfile%\Local Settings\Application Data\pw.exe” /START “%1″ %*
HKEY_LOCAL_MACHINE\SOFTWARE\Clients\StartMenuInternet\FIREFOX.EXE\shell\open\command “(Default)” = "%UserProfile%\Local Settings\Application Data\pw.exe” /START “C:\Program Files\Mozilla Firefox\firefox.exe”
HKEY_LOCAL_MACHINE\SOFTWARE\Clients\StartMenuInternet\FIREFOX.EXE\shell\safemode\command “(Default)” = "%UserProfile%\Local Settings\Application Data\pw.exe” /START “C:\Program Files\Mozilla Firefox\firefox.exe” -safe-mode
HKEY_LOCAL_MACHINE\SOFTWARE\Clients\StartMenuInternet\IEXPLORE.EXE\shell\open\command “(Default)” = "%UserProfile%\Local Settings\Application Data\pw.exe” /START “C:\Program Files\Internet Explorer\iexplore.exe”
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Security Center “AntiVirusOverride” = "1″

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