What does the (state 18) mean
 

Hello !

I am haveing a problem sending email to a certain website . which by chance is just across the street !!!

This is the error message i get :

Delivery to the following recipient failed permanently:

xxxx.xxx.com

Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this error. The error that the other server returned was: 550 550 Requested action not taken: mailbox unavailable (state 18).

What does (state 18) mean ? I have googled and found state 14 and 17's but nothing on state 18.

try to read this link. Maybe it will give the answers. (google -> "mail delivery state 18" -> second page)

http://social.technet.microsoft.com/...1-989d3427b60c