I've just had a new one.
Insufficient Storage
The method could not be performed on the resource because the server is unable to store the representation needed to successfully complete the request. There is insufficient free space left in your storage allocation.
Additionally, a 507 Insufficient Storage error was encountered while trying to use an ErrorDocument to handle the request.
[/b]
This is in addition to the usual one about max user resource reached.
Becoming more and more frequent.
Funny that, came up for me, when I pressed reply.