Perhaps my "should be helpful" was a little too casual. Those are not throw-away suggestions. They are likely the two most common and effective strategies for solving the kind of problem you describe. If you peruse the archives here at Perl Monks you will see them recommended again and again.

They will likely lead you to a solution to your current problem. And checking those two things should become second nature for you any time you have a problem of this sort because they are such reliable strategies.

In particular, find out where your server error log is and befriend it. It is one of your most reliable resources for debugging CGI.