Hi,
I need to activate my program if PrintScreen key is pressed and focus is on some else program.
Thank you.

Stay away from com objects.  You can set up a keyevent monitor in you program, parse the input to determine the key pressed and directly call your program via a shell.  The dotnet framework has all the classes you need to do this.

You can use windows hook to do this

http://www.codeproject.com/csharp/NetWin32Hooks.asp.

Install keyboard hook, check for printscreen key and do your stuff

Stay away from com objects.  You can set up a keyevent monitor in you program, parse the input to determine the key pressed and directly call your program via a shell.  The dotnet framework has all the classes you need to do this.