XP desktop unresponsive

Hi all!
I have a machine that is giving me trouble! It is running XP SP3. The user installed a pc cleaner (by accident, piggybacked on a different app he was installing). During the install, a msg came up stating Windows Explorer had to shut down. Since then, double clicking the mouse on any icon on the desktop will NOT open it. It will flash once, but nothing happens. But you can open all icons by using the right-click/open sequence.

The start button will respond to a single click. When Start/Turn Off Computer/Turn off or Restart is selected, it simply goes back to the desktop. Trying to access Control Panel doesn't work. Also goes back to desktop.

Tried to install malwarebytes. The install will crash. During the install, it comes up with a msg "CoCreateInstance failed; code 0x80040154. Class not registered." After clicking on ok 4-5 times, Malwarebytes setup screen comes up and says completed. When click on Finish, another msg comes up "Run time error '372'. Failed to load control 'WebBrowser' from ieframe.dll. Your version of ieframe.dll may be outdated. Make sure you are using the version of the control that was provided with your application". When clicking ok, the same msg will return in a few seconds. Click ok and it goes away.

I was able to run an AVG scan, but it found nothing. I tried uninstalling ie8 and reinstalling to correct the dll problem but got nowhere.

I'm thinking the registry is corrupt, but do not know how to proceed?
Any ideas?

Thanks in advance!!

 

any time you cannot install malwarebytes, you can be sure that there is malware on the system.

you should try to install in safe mode with networking.

And you should uninstall the cleaner and the app it piggybacked on.

Download, install, update and do full scan with these free malware detection programs:

Malwarebytes (MBAM): http://www.malwarebytes.org/products/malwarebytes_free
SUPERAntiSpyware: (SAS): http://www.superantispyware.com/

Remove all found, reboot, and run again until scans run clean, these can be removed afterwards if you so choose.
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you should also do a clean boot :

http://support.microsoft.com/kb/310353

do not use the guided help method.
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post back if you are able to install malwarebytes and run a full scan.

AVG is not the best, if you are happy with it ok, but sometimes it will mess up some windows systems.

MSE and Avast free are two good free antivirus'