Sometimes on my pc, I have to press the three a bit separately, instead of simultaneously.
Thanks to Jose Ibarra:
Some malicious software is aware of the methods you are most likely to use to find and remove it (Task Manager, System Restore, Command Prompt, the Internet, Google, etc.)
The malicious software does not want you to use things like Task Manager to find and remove it, so it prevents them from becoming a running process on the system and the process will not launch or the process will be terminated as soon as it does launch.
The malicious software is happiest when it fools you into thinking you have to use System Restore, a Repair Install or just reinstall your XP from scratch to fix your system when none of that is necessary.
You can fool the malicious software (then fix it).
Assuming your Windows is installed on your C drive, using Windows Explorer, navigate to the c:\windows\system32 folder and locate taskmgr.exe.
Copy the taskmgr.exe file and rename the copy something that the malicious software will not recognize. I like to call the copy:
c:\windows\system32\jose.exe
Double click jose.exe and see if the Windows Task Manager window will open now.
The problem is the malicious software will not let the taskmgr.exe be a running process, but it does not know about jose.exe as a running process so
you just outsmart it (I have a feeling that it will know about jose.exe someday though).
That will not "fix" your Task Manager but at least you will know if the Task Manger mechanism works or not (taskmgr.exe still will not launch as it should).
If you are trying to remove some malicious software and need to use Task Manager, you can just launch (double click) jose.exe instead, but your system will still be afflicted until you remove the malicious software.
There are usually a few other things that also won't work that you would probably find out about later, so I recommend you do this:
Reduce the chances of malicious software by running some scans.
Download, install, update and do a full scan with these free malware detection programs then resolve any remaining issues:
Malwarebytes (MBAM):
http://malwarebytes.org/
SUPERAntiSpyware: (SAS):
http://www.superantispyware.com/
These can be uninstalled later if desired.
When the scans run clean, reboot, test your Task Manager and we can fix any other remaining issues.
If things look good, you can delete the c:\windows\system32\jose.exe file.
