Can't add my One.com mail account?

Hello!

Any idea why I canโ€™t connect my One.com mail account (IMAP 993 / SMTP 465) ?

I have the latest Nextcloud 11.0.1 and Mail 0.6.2 from App store.

This is the error I get:

Horde_Imap_Client_Exception_ServerResponse: IMAP error reported by server.
/var/www/nextcloud/apps/mail/vendor/pear-pear.horde.org/Horde_Imap_Client/Horde/Imap/Client/Socket.php - line 4302: Horde_Imap_Client_Socket->_getLine(Object(Horde_Imap_Client_Interaction_Pipeline))
/var/www/nextcloud/apps/mail/vendor/pear-pear.horde.org/Horde_Imap_Client/Horde/Imap/Client/Socket.php - line 4230: Horde_Imap_Client_Socket->_sendCmdChunk(Object(Horde_Imap_Client_Interaction_Pipeline), Array)
/var/www/nextcloud/apps/mail/vendor/pear-pear.horde.org/Horde_Imap_Client/Horde/Imap/Client/Socket.php - line 1749: Horde_Imap_Client_Socket->_sendCmd(Object(Horde_Imap_Client_Interaction_Pipeline))
/var/www/nextcloud/apps/mail/vendor/pear-pear.horde.org/Horde_Imap_Client/Horde/Imap/Client/Base.php - line 1726: Horde_Imap_Client_Socket->_status(Array, 1)
/var/www/nextcloud/apps/mail/lib/Mailbox.php - line 223: Horde_Imap_Client_Base->status(Array, 1)
/var/www/nextcloud/apps/mail/lib/Mailbox.php - line 230: OCA\Mail\Mailbox->getStatus(1)
/var/www/nextcloud/apps/mail/lib/Account.php - line 546: OCA\Mail\Mailbox->getTotalMessages()
/var/www/nextcloud/apps/mail/lib/Account.php - line 577: OCA\Mail\Account->guessBestMailBox(Array)
/var/www/nextcloud/apps/mail/lib/Account.php - line 415: OCA\Mail\Account->getSpecialFolder('trash', true)
/var/www/nextcloud/apps/mail/lib/Account.php - line 611: OCA\Mail\Account->getSpecialFoldersIds(false)
/var/www/nextcloud/apps/mail/lib/Account.php - line 340: OCA\Mail\Account->localizeSpecialMailboxes()
/var/www/nextcloud/apps/mail/lib/Account.php - line 351: OCA\Mail\Account->getMailboxes()
/var/www/nextcloud/apps/mail/lib/Controller/FoldersController.php - line 62: OCA\Mail\Account->jsonSerialize()
[internal function] OCA\Mail\Controller\FoldersController->index(1)
/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php - line 160: call_user_func_array(Array, Array)
/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php - line 90: OC\AppFramework\Http\Dispatcher->executeController(Object(OCA\Mail\Controller\FoldersController), 'index')
/var/www/nextcloud/lib/private/AppFramework/App.php - line 114: OC\AppFramework\Http\Dispatcher->dispatch(Object(OCA\Mail\Controller\FoldersController), 'index')
/var/www/nextcloud/lib/private/AppFramework/Routing/RouteActionHandler.php - line 47: OC\AppFramework\App main('OCA\\Mail\\Contro...', 'index', Object(OC\AppFramework\DependencyInjection\DIContainer), Array)
[internal function] OC\AppFramework\Routing\RouteActionHandler->__invoke(Array)
/var/www/nextcloud/lib/private/Route/Router.php - line 299: call_user_func(Object(OC\AppFramework\Routing\RouteActionHandler), Array)
/var/www/nextcloud/lib/base.php - line 1010: OC\Route\Router->match('/apps/mail/acco...')
/var/www/nextcloud/index.php - line 40: OC handleRequest()
{main}

You should enable the imap-logs as well: https://github.com/nextcloud/mail#imap-logging