For some reason, I need to add a new domain( zimbra

1、Redefine MX record pointing to zimbra

2、Goto admin console add a new domain name(

3、Create new account (

4、And then ,I tried send mail to from gmail ,but got a wrong return

< > : host [*. *. *. *] said: 550 5.1.1
< > : Recipient address rejected: (in reply to RCPT to command)

5、And cannot login through web client, display username and password error

What did I miss important Settings? Tks