SMTP ERROR....some places

[dayjahone]

So, I set up an account in a mail client and it works fine. A friend in a different state, whose mail I host, tries to set it up and gets the following error (Using Thunderbird):

the Message could not be sent because connecting to SMTP server mail.myserver.com failed. the server may be unavailable or is refusing SMTP connections. Please verify that your SMTP server setting is correct and try again, or else contact your network administrator.

Any ideas?

[till]

Maybe he uses a firewall that blocks the connection or his access provider blocks connections on port 25.

[dayjahone]

We tried it on two computers -- I don't think it's a firewall. Hmm... So, i should call his Internet company and see what's up?