I compiled my program using Compaq Visiual Fortran 6.5, the Debug version can run normally but the Release version do not run, I know perhaps there is some bugs in my code , but how can I find it, Why Release version do not run???

The odds are that it is one of 2 problems:

1)The compiler optimization is messing up your code - try lower levels of optimization.

2)You have a memory problem - perhaps an array that is not big enough. When you go past the end it corrupts something. Because the optimized code is arranged differently than the debug code, you are (randomly) corrupting something that makes a difference.