Newly uploaded scripts can contain errors, which cause it to not work properly. The most common error message is: "Internal Server Error -The server encountered an internal error or misconfiguration and was unable to complete your request." There are several reasons that explain why a CGI script does not work:

• Script is not executable
• The first line of your script does not point to the correct Perl path
• Misconfigurated script
• You uploaded the script in binary mode and not in ASCII mode.

By changing permissions in the files on your FTP program, you can make the script executable. In most programs, you can just access file properties and change the permission to 755 (rwxr-xr-x). However, this can vary from program to program and according to the type of script. It is also important that the first line of your script contains the command "#!/usr/bin/perl".
Some scripts, like guestbooks, need extra configuration. We recommend checking the README files which follow the script. These files contain instructions to configure your script correctly.