I am trying to migrate from qmail to postfix. With qmail users can use only their username to login, but in postfix they need the whole email address.

This is going to be a big problem, since all the users use only the username today and will not be able to login without changing this. Is there a way to login with just the username in postfix?

I'm using courier-imap with postfix for my virtual mailbox. Upon reading your urgent need, something that I saw before in pop3d settings came in to my mind and I immediately got back to it. Here, if you are using courier-imap, I'm sharing this.

I edited pop3d file and provided a value for DEFDOMAIN wherein by default has no value.

DEFDOMAIN="@domain.com.ph"

I restarted the daemon and tried to log-in with only the "useranme" without "@domain" using Outlook. Yes, I was able to! And to prove it further, I modified my account settings in Outlook to put only my username, I ran "Test Account Settings", and YES, it really worked!

I used this tutorial to build my postfix server.
http://www.postfixvirtual.net/

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GANI

Fantastic. It worked. Thank you very much!