In my case I had a problem with this file: “wvUmmjkh.dll” so I had to do these things to delete it at all.
1- Download the software “Unlocker” in this link:
2- Restart the computer in Safe Mode (when restart press F8).
3- Once the computer is ready again I went to the directory:
C:\windows\system32\wvUmmjkh.dll and “put the trash can very close” from the file to be deleted, I did it like this because the infected file was linked with the winlogon.exe and the explorer.exe and I had no option as fast as this.
4- Use the “Unlocker” software with the infected file and unlock all the files linked to the virus or spyware. In this moment you have to be very fast and throw the file into the trash basket, if you don’t make it fast, the computer is going to restart (in my case, because I was killing to important processes: winlogon.exe and explorer.exe) and you’ll miss the chance to make it in one simple try, I think that you have 2 or 3 seconds to do this action.
5- Once you finished deleting the file I had to download another program called “HijackThis”:
and began to make a “Do a system scan only” of the disk. When it finished you can see a list of all processes running in your machine, in my case the file “wvUmmjkh.dll” was with an indication of “missing file” so the only thing that I had to do to end all this was to delete the registry who belonged to it, very simply, just check the box and press “fix checked” and the registry will be inmediatly erased.
Just in case, with “HijackThis” you have an option of “Delete on Reboot”, in some cases it works and sometimes not.
My best regards, Milton Martorella.