default email work but user email doesn't with imap auth

I’m new to Virtualmin.
System Spec.
O/S = Ubuntu Server 14.04 LTS x64
Virtualmin = 4.12 gpl

I create a Virtual Server ex.{} and an email/ftp/ssh account is setup as well for user example this works well even with external client email ex {Thunderbird} - No Problems
The problem is that when i create/add user ex.{example1} with Email only i can check the main using usermin@ 20000 but i can not use imap with thunderbird says the password is invalid


You may want to verify that you’re using the correct username. Usermin can be forgiving regarding the username, but when using another client, it needs to be exact.

You can determine the username to use by going into Edit Users.

There, you’ll see the username to use under the “IMAP / POP3 / FTP login” field.


i figured it out
when setting up thunderbird have to use the postfix user name of {username.domainname}