I can't open command prompt also

[chandana09458]

"This application was unable to start correctly (0xc000012). Click OK to close this application." Not even a pdf file is opening.

 

[Alabalcho]

And your computer is ....
And your version of Windows is ...
And the application is ...
Aid it used to work before I installed ....

 

[chandana09458]

And your computer is ....lenovo
And your version of Windows is ..8.1
And the application is ...all applications except control panel is not starting
Aid it used to work before I installed ....

teamviewer along with avg antivirus

 

[Alabalcho]

So - revert to state before installing TV and AVG, and see what happens.