HTTP error 503 The service is unavailable. Horde is unavailable while the system is setting the hostname

[NickTheGreek 160]

for cPanel / WHM based WebMail (Horde)

Sometimes Horde won’t work after a cpanel update. You may receive below error, while accessing Horde.

HTTP error 503 The service is unavailable. Horde is unavailable while the system is setting the hostname.

Solution 1:
1. Make sure hostname is correct.

/usr/local/cpanel/scripts/check_valid_server_hostname

Solution 2:

1. ssh in to the server.
2. cd /var/cpanel/.application-locks
3. rm UpdateHostname\:USERNAME
4. /usr/local/cpanel/bin/update_horde_config –user=USERNAME

https://techsemi.wordpress.com/2016/11/08/horde-is-unavailable-while-the-system-is-setting-the-hostname/

https://forums.cpanel.net/threads/horde-wont-load-after-update-to-11-52.503071/