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This will sometimes cause Perl to spit out exactly what the issue is.
For PHP Scripts:
After you are positive that you have uploaded your PHP scripts in binary mode and have set the permissions correctly (usually 644 or 444)? Also, due SuExec installed on most of our servers, folders must have 755 permissions set.
View the error logs!
Did you know that your control panel has error logging enabled?
This lets you see where the script might be failing as well.
Log into the control panel and select Stats > Error Log.
You might even see "error_log" in the same directory that your scripts run in. This can be a good place to start.
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