Wrong error: Maintenance Mode is On

[Huster-at-github]

• NC 11.0.1
• Ubuntu 16.04 LTS

Want to update app Audio Player. Get this error:

And logging says that I'm in maintenance mode. But I'm for sure not!

Fatal webdav Sabre\DAV\Exception\ServiceUnavailable: HTTP/1.1 503 System in maintenance mode.

[internal function] OCA\DAV\Connector\Sabre\MaintenancePlugin->checkMaintenanceMode(Object(Sabre\HTTP\Request), Object(Sabre\HTTP\Response))
/var/www/nextcloud/3rdparty/sabre/event/lib/EventEmitterTrait.php - line 105: call_user_func_array(Array, Array)
/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 466: Sabre\Event\EventEmitter->emit('beforeMethod', Array)
/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 254: Sabre\DAV\Server->invokeMethod(Object(Sabre\HTTP\Request), Object(Sabre\HTTP\Response))
/var/www/nextcloud/apps/dav/appinfo/v1/webdav.php - line 60: Sabre\DAV\Server->exec()
/var/www/nextcloud/remote.php - line 165: require_once('/var/www/nextcl...')
{main}
2017-02-04T16:47:59+0100

[Huster-at-github]

Now 4 App Updates are pending .... :-(

But I have other issues too:

• Cannot send E-Mails with app Mail
• Amazon S3 no more working

[Flole998]

When upgrading apps your site gets automatically put in maintenance mode. That is intended and not an issue. Your logs are incomplete and do not show the update but instead a webdav request.

[tcitworld]

FYI, it happened to me after migrating my instance to another server.
I resolved this by updating all the apps, putting nc in maintenance mode on and off, and then files:scan.