email id showing like this "username.domainname@domainname"

when i am accessing webmail using usermin https://domainname:20000/.but its showing different domain name.If i am accessing that domain using webmail ( i can send emails but its showing like this ""



When you access webmail using "", what webmail program is that using?

Ah, while Usermin can detect your email address, most other email clients can't do that.

If you're using Squirrelmail, you may need to go into the Squirrelmail settings in order to set the From address for your email users.