Recover accidentally deleted mspaint.exe/notepad.exe etc.

A. Goto "%windir%\System32\DLLCache" folder and look for the file, if its there then copy it to "%windir%\System32\" folder.

B. Insert your Windows Setup CD and goto "I386" folder. Now look for the same file, it'll present there but the last letter of extension will be "_". e.g., u'll get "mspaint.ex_"/"notepad.ex_"/etc. Now open Command Prompt and goto "I386" folder and give following command:

expand mspaint.ex_ mspaint.exe
expand notepad.ex_ notepad.exe
etc.

Now u can copy the file to "%windir%\System32" folder.

C. Give following command in Command Prompt:

sfc /SCANNOW

It'll automatically restore the files.