You may disable encryption only with
Make sure you have backups of all the encryption keys, including those for all users.
When you do, put your ownCloud server into single-user mode, and then disable your encryption module with this command:
sudo -u www-data php occ maintenance:singleuser --on sudo -u www-data php occ encryption:disable
|Encryption cannot be disabled without the user’s password or file recovery key. If you don’t have access to at least one of these then there is no way to decrypt all files.|
When decryption has finished, disable single-user mode, using the following command.
sudo -u www-data php occ maintenance:singleuser --off
It is possible to disable encryption with the file recovery key, if every user uses them. If so, decrypt-all will use it to decrypt all files.