- The domain's root folder in /var/www/vhosts was not owned by the domain user. So I fixed that with a chown command.
- Within the Plesk control panel, I had to disable "Perl" support and enable "CGI" support to get my perl scripts with the ".pl" extension to run under cgi-bin
After an upgrade to Plesk 11, my Perl scripts located under cgi-bin/ for a specific domain were not executing properly. Requests generated HTTP response code 500 and my error logs showed the unhelpful message "Premature end of script headers" I verified all permissions and even disabled / re-enabled cgi-bin support through Plesk which installs a test script under cgi-bin/test/test.cgi Even the test script failed to run. It also generated the message "Premature end of script headers: test.cgi" I eventually resolved the issue with two changes: