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What is an Internal Server Error (Error 500)?

This is a general error message that your web server sends back that means a script could not run for some reason. Usually you can find out why by checking your web server logs. Other things you can check are:

1. File Upload Mode: Did you upload your Perl script in ASCII mode? Your FTP client may have uploaded the script in binary mode if you did not take any special action. Perl scripts are ASCII files, and since different operating systems have different ways of representing the end of line character (for example: Unix uses a line-feed, Windows uses a carriage-return and line-feed pair), it is important that you set the uploading method to ASCII, so that line-end translation is performed.
Re-upload the script, this time making sure that it was uploaded in Text or ASCII mode. If you are using a Windows FTP program like WS_FTP, make sure that the radio button "ASCII" is selected and not "Binary" or "Auto". Do not use any auto-detection options since the FTP program might assume the extensions you are using for your scripts are for binary files.

2. File Permissions: Did you change the permissions on your script so that it can be executed on your web server? In most cases, simply uploading the Perl script to the server does not necessarily mean that it can run. On Unix web servers (like Linux, BSD, Solaris, etc), it is necessary to change the file permissions to indicate to the operating system that the file may be executed. If you have a Unix FTP client, set the permission ("chmod") of the file to 755, which allows the script to be executed by everybody. If you are using FTP software to upload your scripts, you can usually right-click the file that you've just uploaded and choose "chmod" or "permissions", and change them to 755.

3. Check Modifications: If you actually had to modify the script to configure it, did you introduce new errors into the script? If you are not the author, get another copy of the original script (prior to your changes) and compare it with your current script. Perhaps you forgot to place a semi-colon (";") after a particular variable assignment.

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