I've tried all of the above to open my task manager and nothing works. I don't get any errors it just never opens. I've checked the registry key already and it is not set to 'Disable'.
For Windows 7 you can check your registry for this path and make sure it is set correctly. Follow the steps below to open your task manager.
Now that your Registry Editor is open. Browse to the location below. You should be able to find the folder called taskmgr.exe as shown below at the end of the registry string. If you find the folder, your done with this part of the check. If you DO NOT find the folder called taskmgr.exe, then create one by right clicking on the folder called "Image File Execution Options" and then choose New, Key and name it taskmgr.exe. You might have to reboot to make the changes take effect and then test your Task Manager again.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\taskmgr.exe
If the task manager fixes failed, you can use Process Explorer as a work around until you get the virus removed, then try the fix again. It works the same as Task Manager. Process Explorer is owned by Microsoft. You can download Process Explorer from Microsoft by clicking on this link to visit the Microsoft.com Download Page
If you cant download or do not want to use Process Explorer. Use your command prompt as the task manager to end processes.
You can look at all running process in the command prompt following the steps below:
This probably won't work is it's probably a deeper underlying issue, but try
As an alternative to the task manager try Process Explorer