503 Error

[vmbelizario]

Hello,

I have a Plesk 12 on a Centos 6.6 Server. I have 3 domains on this server, and one of this domains only some pages give me a 503 error - and i cant find where fix It.

I tried to do:
Plesk Control Panel : Websites & Domains > mydomain.com > Web Server Settings > Put ErrorDocument 503 /custom_error.html

/etc/httpd/conf/plesk.conf.d/server.conf : add the ErrorDocument 503 /custom_error.html on virtual host of this domain

Edit the /var/www/vhosts/system/mydomain.com/conf/last_httpd.include file and add the line ErrorDocument 503 /custom_error.html on my domain

edit
/var/www/vhosts/mydomain.com/error_docs/maintenance.html file

edit
/var/www/error/HTTP_SERVICE_UNAVAILABLE.html.var file

create a
RewriteRule^.*$ https://www.mydomain.com/404-page/ [R=503,L]
ErrorDocument503 https://www.mydomain.com/404-page/

in .htaccess,
it worked, the error redirect to 404 page ( a nice page) but the home page redirect to 404 too.

Can someone help me ?