You cannot use an ISP that you are not connected to.

Error 550:
http://www.insideoe.com/problems/errors.htm#relay550
--
Bruce Hagen
MS-MVP Outlook Express
~IB-CA~

"dshadow06" wrote in message
news
I can receive mail from all isp's but I can only send mail to my own
accounts. I have followed work around instructions and deleted mail box,
called isp and have checked all settings. checked firewall settings and
outlook express is exempt. outgoing virus for mails is turned off. I still
cannot send email using outlook express 6, am also using IE 7. The
following
message is typical, only the isp names change.
The message could not be sent because one of the recipients was rejected
by
the server. The rejected e-mail address was '. Subject
'The
Sentinel: Top Stories', Account: 'pop.charter.net', Server:
'SMTP.charter.net', Protocol: SMTP, Server Response: '550 relaying mail to
aol.com is not allowed', Port: 25, Secure(SSL): No, Server Error: 550,
Error
Number: 0x800CCC79