What happened !!!???

I was writing a program in turbo c++ version3 in which the user has to type in 'exit' to leave the program. The program displays 'press any key to exit... ' and waits for getch() and comes back to the coding screen. But the program exits out of the c++, DOS mode and returns to windows displaying the foll error msg

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The program tried to execute an invalid instruction.

Fault Location: 0000:5481
Interrupts in service: None
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:confused:

I go back to dos mode and again run the program from the c++ edit window this happens again
:mad:

SOMEBODY TELL ME WHATS WRONG

post your code