Unable to run .exe files

I'm quite sure i downloaded a virus (well when i eventually managed to do a scan there were something like 5000 issues!!).
To start off with my computer restarted and would not load, the blue screen came up saying windows had shut down to protect my files.
So I restarted it again and before the blue screen there was options to load in safe mode (some other variations of safe mode) normal windows and to load windows using the last settings that worked, I tried normal windows first and that came up with the blue screen again, however the third time I noticed the last working settings option and that loaded windows, or rather I was logged on but the only thing there was my desktop picture, so I Ctrl + Alt + Del and got the task manager and tried run explorer.exe and it came up with the error sign saying windows doesn't know what program to run this with so either choose from list of programs or search the internet, so first I try and use explore.exe to run explorer.exe, and yea that didn't work. I managed to get windows (sort of) working by trying to open things from my Firefox download list using explorer.exe and now i have my desktop files and the start bar and can open folders but and programs won't work, i managed to run a scan using my McAfee by right clicking on my computer and clicking scan it treated about 5000 something. I restarted my computer and this time windows ran but with the same issues, I can run regedit because it is a .exe and I can't open any other program. i have read some other posts and they mention iexplorer.exe that isn't running on my computer (that I'm aware of) and I can't find the file.
oh and also hidden files wont unhide themselves.

To solve manually:
To open regedit, go to computer/your OS (should be x64 or C:/)/windows
Then hit the letter 'R' until you see the icon for REGEDIT... Right click this, and choose run as: Then choose your local admin, on the user that you are currently logged into. Don't worry about a password unless your account requires one... Simply provide that if needed.

Then, from there.... This is where it gets a little tricky.
  • Choose:

  • Then navigate yourself to the right pane....
  • There should be two things we are looking for here... The first is our SHELL... find that and double-click (or right click then choose 'modify') the value data should read EXACTLY THIS: explorer.exe If it does NOT say this, or says ANYTHING else, change it so that is says simply: explorer.exe

  • Scroll down in the same pane, and find Userinit... Modify this as well... The value data should read exactly this: C:\Windows\system32\userinit.exe,

Yes... There should be a comma. If this value is NOT set exactly as I mentioned... Modify it to that. *Close the registry editor, and do a power cycle (restart your PC, shutting it down completely, turn it off, then turn it back on using the button... Do not simply click restart)
This should give you explorer.exe back.
  • After that, you will still have issues opening programs... There is no easy fix for this, so I'll give you the short answer.
  • Create a new user by going to CONTROL PANEL.
  • Give that new user Admin. Permissions
  • Load em up.
  • Put all of your important icons on a memory stick or external HD
  • Make sure all of your programs work
  • Delete the previous user.
  • This should fix all of your problems.

Total estimated fix time: 20 minutes

This is a complete fix.... There should be no residual issue after completing these steps.

Faster solution:
This works on the rundll32 error

Download this fix: http://www.dougknox.com/xp/fileassoc/xp_exe_fix.zip
Thanks to AdamDanger for this tip on the forum.
Published by aakai1056. Latest update on April 27, 2010 at 04:57 AM by aakai1056.
This document, titled "Unable to run .exe files," is available under the Creative Commons license. Any copy, reuse, or modification of the content should be sufficiently credited to CCM (https://ccm.net/).
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