Mail not sending, server offline, since Lion

Mac SMTP server offline (Solved problem)

My SMTP server has been offline for 5 weeks. I have spent in excess of 10 hours on the phone with Suddenlink (my mail provider). Spoke to 6 different techs. They changed everything, but nothing worked. Googled mac+smtp server offline and spent another 5 hours searching, trying almost everything anyone suggested...nothing worked.

Googled Suddenlink+mac+smtp server offline. Found the answer. In my case it was very simple. The SMTP server user name had been changed by one of the techs and it was wrong. It should have been my complete email address. Corrected it and I can now send emails.

When you do a search...type in the name of your mail provider first+mac+smtp server offline. It made a huge difference in the answers.

Hope this helps.

This may help

Do not know, if this will help others, but after spending 3 hours trying to set up my wife's new MacBook Air to send SMTP mail, finally succeeded. Everytime we correctly set the smtp server name/address the MBA would add Offline and would not send the email.
Finally I left the "smtp.ourprovideraddress.com (Offline)" as one of the outgoing servers AND added "smtp.ourprovideraddress.com" as a second smtp server. This time the system did not put this one offline. I then selected this new smtp server and checked the "use only this server" box. The outgoing mail was send and further outgoing emails are sent. Try it, might work for you as well.