I am unable to delete mail folders in Horde. I may have gone about deleting email addresses incorrectly as I first deleted in CP and now am unable to delete in Horde.

The following is reported:-

The folder "xxxxxxx@xxxxx_biz" was not deleted. This is what the server said: Mailbox does not exist, or must be subscribed to.

or

The folder "xxxxxxx@xxxxxx_com" was not deleted. This is what the server said: Cannot delete this folder.

Can anyone assist!