We hope that we can have a better webmail client for windows server hosting.
at least it must be allowed admin to set the mailbox quota, user changing password...

The problem is windows don't have good mail servers fully supporting imap. All good webmails are based around imap.So far UebiMiau is the only powerful webmail compatible with Helm & mail server.

i remembered that my previous provider was using the imail. it is great... it allows users to manager thier own email account.

Thank you. We'll consider your proposition.

Try looking at lumisoft mailserver. It is written in .Net and supports IMAP...and it's free including source code. http://www.lumisoft.ee

does it support users change thier info & password?

astral:

To answer your question, no, the webmail interface is fairly primitive.

What exactly is the requirement, a mail server or a web mail client? or both?

Lumisoft have both.