unresponding problems in windows 7

[frdrck]

why is it that when you are using any program, it comes to a time and this error starts coming on the screen that not responding and windows needs to close?

 

[Hawkeye22]

Anytime a program is running an intensive process, it may not respond to the UI (user interface). When this happens for too long a period of time, windows flags it as non-responsive. Sometimes the program is truly hung up and needs closed. Other times, if the program is not stuck and you wait long enough, the program will become responsive again.