email no such person here

I have very strange problem.
I have an email with name example: booking@domain.
I already set up this email at cpanel.
But, tomorrow, when people send the email to booking@domain, it always bounce with error: no such person here. Even those email was exist.

And this happen to all domain in this server. All domain can't receive email even the user is exist.

But, when i try to create 1 account at 1 domain. All email at all domain works fine.

But it happen everyday. So i have to do this everyday.
Can you help me please?

Thanks

 

Everything just fine. DNS and MX record is good. When i tail -f exim_mainlog, here is the message:

2008-07-23 19:14:17 H=ti-out-0910.google.com [209.85.142.190] Warning: Sender rate 0.0 / 1h
2008-07-23 19:14:17 H=ti-out-0910.google.com [209.85.142.190] F=<info@*******.com> rejected RCPT <booking@******.com>: No Such User Here

It happen every day. If i force to exim update, it can work again. But should i do this everyday? i dont think so.

I can login to through webmail with this email user. But when try to send message, the error show this:

Message not sent. Server replied:

Authentication failed
535 Incorrect authentication data

What i have to do again? My datacenter even can't resolve this problem.
Thanks

 

I try to saw at the mail folder. And its very strange.

like this (hidden the owner of the account):

lrwxrwxrwx 1 28 Jul 25 23:17 .mail_name@domain_com -> domain.com/mail_name
drwxr-x--- 3 2048 Jul 25 23:17 domain.com
drwx------ 2 2048 Jul 21 03:51 cur
drwx------ 2 2048 Jul 21 03:51 new
drwx------ 2 2048 Jul 21 03:51 tmp

at another server, there's no lrwxrwxrwx 1 28 Jul 25 23:17 .mail_name@domain_com -> domain.com/mail_name

Is there any different with the exim?