I can only receive email cannot send new mail with outlook express 6.0
installed in my laptop connecting to a ADSL connection. The following error
message appears after my sending :

The message could not be sent because the server rejected the sender's
e-mail address. The sender's e-mail address was '.
Subject 'test', Account: 'imail.hcm.fpt.vn', Server: 'omail.hcm.fpt.vn',
Protocol: SMTP, Server Response: '550 you cannot access
from current location', Port: 25, Secure(SSL): No,
Server Error: 550, Error Number: 0x800CCC78

I creat the same account and be able to send/receive with OE 6.0 in another
home PC connecting to another ADSL service.

When I telnet omail.hcm.fpt.vn 25 the result in my laptop is:
220 hcm.fpt.vn Power Mail version 2.13 [50]

I creat the same account in Microsoft Outlook installed in laptop but can
not send also (receiving is Ok).

I can send and receive with different email account (different outgoing and
incoming server) by OE or MO.

Please give me an instruction how to solve. I need to use OE for
send/receive email by the above email account. Thank you very much for your
help!!!