Fehlender Index "fs_storage_path_prefix" in der Tabelle "oc_filecache".
Fehlender Index "fs_id_storage_size" in der Tabelle "oc_filecache".
Fehlender Index "properties_pathonly_index" in der Tabelle "oc_properties".
Fehlender Index "job_lastcheck_reserved" in der Tabelle "oc_jobs".

• ERROR:

  OC\HintException: [0]: Memcache \OC\Memcache\APCu not available for local cache (Is the matching PHP module installed and enabled?)

• FIX:

  nano /etc/php/x.x/cli/php.ini -> append "apc.enable_cli = 1"
  cd /var/www/html/nextcloud

  sudo -u www-data php occ db:add-missing-indices

• comment out createBackup in updater.php

  case 3:
    //$updater->createBackup();
    break;

• Disable e2e plugin
• delete all encrypted folders (via ssh)
• remove appdata_[your installation id]/end_to_end_encryption/*
• mysql> oc_e2e_encryption_lock;
• DELETE FROM oc_filecache WHERE path LIKE “%[your old e2e folders]%”;