Undelivered Mail Returned to Sender

[duy_dang2110]

Hi all ,
My host has an email account , when other person send mail to this account a message return :

This is the mail system at host xxxxx.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

The mail system

<[email protected]>: host x.x.x[x.x.x] said: 550 "Unknown
User" (in reply to RCPT TO command)

All other account is normal , even I delete and create this account many time but it still get this error .

 

[duy_dang2110]

I check my maillog and saw:

3-11-30 08:21:51 H=x.x.x (x.x.x) [x.x.x.x] F=<[email protected]> rejected RCPT <[email protected]>:
2013-11-30 08:21:51 H=x.x.x (x.x.x) [x.x.x.x] incomplete transaction (RSET) from <[email protected]>

 

[nobaloney]

UNKNOWN simply means that the receiving server either doesn't hot email for the domain, or if it does, that the email address doesn't exist on the server.

You should verify that you're sending to the correct server and that the email address really exists on that server. Once you've done that, then you'll need to be in touch with the postmaster of that machine to try to find the problem; it will be in the recipient machine logs.

Jeff