Mail, outgoing server shut down, incoming mail is working

Question

I can't send mail. When sending, I get a message that outgoing server is shut down. I have no problem receiving mail.
I installed Mountain Lion a few days ago (on my MBP), dont know if there is a connection?. I have the same problem
on my iMac. I have not installed Mountain Lion on the iMac. I called the provider (telia). The say they don't have any problem.
I connected to web mail and sent mail from there. It worked.
I would be grateful for suggestions how to find the problem.
Thanks in advance!

Answer 1

How is your Mail preferences set up for outgoing? Port 25? No authentication? SSL checkbox not checked? And I assume you mean that you can send email when you are at home when your computer is affiliated to your wireless router, not that you specified 192.168.1.1 or whatever as your smtp server in Mail's setup. If your outgoing mail server is through an email account provided by your ISP, they frequently do not require authentication because they can authenticate on the fact that your IP address belongs to their pool of IP addresses -- when you are at home. But when you aren't home, then you are trying to relay mail from a "foreign" IP address through their server -- and if the mail isn't going to one of their accounts, they block those, otherwise every spammer in the universe would be relaying spam through their servers. I would try changing your outgoing mail config to port 587 with username/password authentication and SSL checkbox checked. I would try similar changes on the incoming side, SSL checked and port 993 if imap or 995 if pop -- if you leave it 143 or 110 without SSL then your incoming mail traffic, including you sending your password, is done "in the clear." The SSL settings should work whether you are at home or on the road. If they don't work, contact your email provider and ask them how to set up a common configuration that works from home and anywhere else.