Article ID: 121491, created on May 7, 2014, last review on Jun 17, 2016

  • Applies to:
  • Plesk for Linux/Unix
  • Plesk 12.5 for Windows


Some domains need a significant period of time to load and eventually fail with a 500 Internal Server error.

In the domain specific log /var/www/vhosts/domain.tld/logs/error_log, there are the following messages:

[Thu Oct 10 12:52:18 2013] [warn] [client] mod_fcgid: can't apply process slot for /var/www/cgi-bin/cgi_wrapper/cgi_wrapper
[Thu Oct 10 12:52:18 2013] [error] [client] File does not exist: /var/www/vhosts/domain.tld/httpdocs/owncloud/favicon.ico
[Thu Oct 10 12:52:18 2013] [error] [client] File does not exist: /var/www/vhosts/domain.tld/httpdocs/owncloud/owncloud


If the 'can't apply process slot for' error messages are in the error log, this means that the FcgidMaxProcesses limit has been reached.

It is not a server performance issue but an issue in communication between Apache and its module.


  1. Increase the 'FcgidMaxProcesses' value in 'fcgid.conf' and restart Apache.

    Location of the file is as follows:

    '/etc/httpd/conf.d/fcgid.conf' for Red Hat-like operating systems,

    '/etc/apache2/mods-enabled/fcgid.conf' for Debian-like operating systems.

  2. After that, restart the Apache service:

    for Debian-like operating systems:

    # service apache2 restart

    for Red Hat-like operating systems

    # /etc/init.d/httpd restart
  3. If the above solution did not help, try using Nginx+FPM combination.

    If you have Nginx and PHP-FPM installed via autoinstaller (/usr/local/psa/admin/bin/autoinstaller) you can enable PHP processing by Nginx+PHP-FPM for a particular domain:

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  4. Re-create Apache configuration files:

    # /usr/local/psa/admin/bin/httpdmng --reconfigure-all

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Warning: SuexecUserGroup directive requires SUEXEC wrapper

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