Webserver

Apache/nginx incorrect behavior and everything else related to Web.

Website hosted in Plesk is displayed incorrectly, shows 503 Internal Server Error or returns a PHP warning: Failed to read session data
Webserver Configurations Troubleshooter detects extra configuration or shows a false positive report on the Home page
nginx fails to start on the Plesk server: 99: Cannot assign requested address
Apache restarts frequently on a Plesk server: Caught SIGTERM, shutting down
How to update web server settings via CLI for all domains on Plesk for Linux server?
nginx fails to start/reload on a Plesk server: Too many open files
Website hosted on Plesk for Windows server is not accessible: 500 Internal Server Error: An ASP.NET setting has been detected that does not apply in Integrated managed pipeline mode
Website hosted in Plesk shows 403 Forbidden or blank page: pcfg_openfile: unable to check htaccess file, ensure it is readable
Website PHP files are downloaded instead of executing in a server with Plesk
Websites on Plesk server are slow or show error 500 or PHP mail cannot be sent: ap_pass_brigade failed
Apache config file cannot be generated on a Plesk server: Wrong variable to subsitute
Error message on the Home page in Plesk: module unique_id_module is already loaded, skipping
After dist-upgrade Apache was upgraded from 2.2 to 2.4, Apache and cannot start
Plesk websites are inaccessible with 504 Gateway Timeout with enabled firewall: : Connection timed out
Unable to start nginx: Not starting nginx as it is disabled in config
Apache failed to start: (24)Too many open files: Init: Can't open server certificate file
Plesk domain shows 403 Forbidden: Symbolic link not allowed or link target not accessible
Can't reconfigure Plesk domain: Invalid parameter number: no parameters were bound
Website hosted in Plesk is unavailable: Invalid command 'php_flag' or 'php_value'
Various actions fail in Plesk: The prefix '/var/www/vhosts/system/example.com' does not exist or is not a directory, FPM initialization failed
Unable to start Apache: Duplicated Listen entries in Apache configuration file
How to secure Plesk interface with an SSL certificate (Let's Encrypt / other certificate authorities)
Can't upload large files over PHP in Plesk: HTTP request length exceeds MaxRequestLen
Errors appear on a Plesk server in Apache log: RSA server certificate does NOT match server name
Website hosted in Plesk for Windows fails to load: The FastCGI process exceeded configured activity timeout
How to create a domain forwarder in Plesk?
Unable to start Apache/nginx on a Plesk server: AH02291: Cannot access directory for error log of vhost
Roundcube/Horde webmail and websites on FastCGI are not accessible: Connection reset by peer: mod_fcgid: error reading data from FastCGI server
A website or webmail does not work on a Plesk for Windows server: Error 503. The service is unavailable
How to restart Apache service in Plesk for Linux