When using Plesk PHP 5.3.x, php pages in plesk will be throwing internal server error. when you select the PHP handler as CGI/FCGI, you will be finding the following error message in the Apache logs.
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Premature end of script headers: cgi_wrapper (13)Permission denied: exec of ‘/usr/sbin/suexec’ failed
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To resolve the issue, change the ownership of the plesk suexe ‘/usr/sbin/suexec’ as follows: “root:apache”
Previously, the ownership will be as follows: “root:root”
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