Error during app service registration: Class 'Horde_Translation' not found

After a recent update of Nextcloud on one of my Arch Linux based servers I’m seeing lots of error messages in the log file that say Error during app service registration: Class 'Horde_Translation' not found. I can no longer access the user settings page, for instance.

Looking at the file system tree I can see that Horde is shipped with the mail app under apps/mail/mail/vendor/pear-pear.horde.org but I’m not sure if that suffices.

Any idea what went wrong here?

I forgot to mention that I’m running nextcloud 23.0.0 with php7 and fpm.

FWIW, the same issue occurs with php8.

And occ from the command line yields this:

$ php occ app:update 
An unhandled exception has been thrown:
Error: Class "Horde_Imap_Client" not found in /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php:106
Stack trace:
#0 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(106): ReflectionClass->newInstanceArgs()
#1 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(114): OC\AppFramework\Utility\SimpleContainer->buildClass()
#2 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(131): OC\AppFramework\Utility\SimpleContainer->resolve()
#3 /usr/share/webapps/nextcloud/lib/private/AppFramework/DependencyInjection/DIContainer.php(463): OC\AppFramework\Utility\SimpleContainer->query()
#4 /usr/share/webapps/nextcloud/lib/private/AppFramework/DependencyInjection/DIContainer.php(435): OC\AppFramework\DependencyInjection\DIContainer->queryNoFallback()
#5 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(56): OC\AppFramework\DependencyInjection\DIContainer->query()
#6 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(182): OC\AppFramework\Utility\SimpleContainer->get()
#7 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(160): OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#8 /usr/share/webapps/nextcloud/3rdparty/pimple/pimple/src/Pimple/Container.php(114): OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#9 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(127): Pimple\Container->offsetGet()
#10 /usr/share/webapps/nextcloud/lib/private/AppFramework/DependencyInjection/DIContainer.php(457): OC\AppFramework\Utility\SimpleContainer->query()
#11 /usr/share/webapps/nextcloud/lib/private/AppFramework/DependencyInjection/DIContainer.php(435): OC\AppFramework\DependencyInjection\DIContainer->queryNoFallback()
#12 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(87): OC\AppFramework\DependencyInjection\DIContainer->query()
#13 [internal function]: OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#14 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(106): array_map()
#15 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(114): OC\AppFramework\Utility\SimpleContainer->buildClass()
#16 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(131): OC\AppFramework\Utility\SimpleContainer->resolve()
#17 /usr/share/webapps/nextcloud/lib/private/AppFramework/DependencyInjection/DIContainer.php(463): OC\AppFramework\Utility\SimpleContainer->query()
#18 /usr/share/webapps/nextcloud/lib/private/AppFramework/DependencyInjection/DIContainer.php(435): OC\AppFramework\DependencyInjection\DIContainer->queryNoFallback()
#19 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(87): OC\AppFramework\DependencyInjection\DIContainer->query()
#20 [internal function]: OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#21 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(106): array_map()
#22 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(114): OC\AppFramework\Utility\SimpleContainer->buildClass()
#23 /usr/share/webapps/nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(131): OC\AppFramework\Utility\SimpleContainer->resolve()
#24 /usr/share/webapps/nextcloud/lib/private/AppFramework/DependencyInjection/DIContainer.php(463): OC\AppFramework\Utility\SimpleContainer->query()
#25 /usr/share/webapps/nextcloud/lib/private/ServerContainer.php(145): OC\AppFramework\DependencyInjection\DIContainer->queryNoFallback()
#26 /usr/share/webapps/nextcloud/lib/private/Console/Application.php(217): OC\ServerContainer->query()
#27 /usr/share/webapps/nextcloud/lib/private/Console/Application.php(128): OC\Console\Application->loadCommandsFromInfoXml()
#28 /usr/share/webapps/nextcloud/console.php(98): OC\Console\Application->loadCommands()
#29 /usr/share/webapps/nextcloud/occ(11): require_once('/usr/share/weba...')
#30 {main}

This is very much a default install without any tweaks.

Resolved by disabling the Mail app.

Hi
Disabling Mail, is this a solution when using it?
I have Mail installed, and I get this message after last update to 2.2.6 running in AiO.

[mail] Fatal: Error: Class "Horde_Translation" not found at <<closure>>
0. /var/www/html/lib/private/AppFramework/Bootstrap/Coordinator.php line 136
   OCA\Mail\AppInfo\Application->register(["OCP\\AppFramew ... "])
1. /var/www/html/lib/private/AppFramework/Bootstrap/Coordinator.php line 91
   OC\AppFramework\Bootstrap\Coordinator->registerApps(["files","activi ... "])
2. /var/www/html/lib/base.php line 671
   OC\AppFramework\Bootstrap\Coordinator->runInitialRegistration()
3. /var/www/html/lib/base.php line 1144
   OC::init()
4. /var/www/html/ocs/v1.php line 31
   require_once("/var/www/html/lib/base.php")
5. /var/www/html/ocs/v2.php line 23
   require_once("/var/www/html/ocs/v1.php")

PUT /ocs/v2.php/apps/user_status/api/v1/heartbeat?format=json
from 93.5.120.234 at 2023-04-24T08:31:50+00:00

On another hand, I’m not receiving email notifications since a few days, and the test password from Admin > Basic settings, is said to be sent but never gets to my mail box.

Could one guide me towards the appropriate error message that could help me find out the origin of the issue, please?

Have a good day