Mail Account Create - Request failed with status code 500

When creating an email account in Nextcloud Mail with a Sasktel.net email (regional phone company) I get the Status Code 500 error. It does work on all other mail clients. Somehow Iā€™m guessing the error is something being mishandled in the mailbox listing, as your PHP code is erroring on an explode() call. After the error, the account is created, but there still is no folder listings available.

Nextcloud 22.2.0 - Mail 1.10.5

Nextcloud Log:
|Error|mail|TypeError: explode() expects parameter 1 to be string, null given

  1. /var/www/html/nextcloud/apps/mail/lib/IMAP/FolderMapper.php - line 239:explode()
  2. /var/www/html/nextcloud/apps/mail/lib/IMAP/FolderMapper.php - line 218:OCA\Mail\IMAP\FolderMapper->guessSpecialUse()
  3. /var/www/html/nextcloud/apps/mail/lib/IMAP/FolderMapper.php - line 174:OCA\Mail\IMAP\FolderMapper->detectSpecialUse()
  4. /var/www/html/nextcloud/apps/mail/lib/IMAP/MailboxSync.php - line 113:OCA\Mail\IMAP\FolderMapper->detectFolderSpecialUse()
  5. /var/www/html/nextcloud/apps/mail/lib/Service/MailManager.php - line 139:OCA\Mail\IMAP\MailboxSync->sync()
  6. /var/www/html/nextcloud/apps/mail/lib/Controller/PageController.php - line 129:OCA\Mail\Service\MailManager->getMailboxes()
  7. /var/www/html/nextcloud/lib/private/AppFramework/Http/Dispatcher.php - line 217:OCA\Mail\Controller\PageController->index()
  8. /var/www/html/nextcloud/lib/private/AppFramework/Http/Dispatcher.php - line 126:OC\AppFramework\Http\Dispatcher->executeController()
  9. /var/www/html/nextcloud/lib/private/AppFramework/App.php - line 156:OC\AppFramework\Http\Dispatcher->dispatch()
  10. /var/www/html/nextcloud/lib/private/Route/Router.php - line 301:OC\AppFramework\App::main()
  11. /var/www/html/nextcloud/lib/base.php - line 1000:OC\Route\Router->match()
  12. /var/www/html/nextcloud/index.php - line 36:OC::handleRequest()|
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