Mail account show [email protected](Offline) can send emails

Last week I stopped being able to send emails out from mac.mail. Everything was working fine one minute and the next, I haven't been able to send out mail. Thanks very much for your help.

I am able to send mail through the MobleMe Account but not through Mail.

First checked to make sure email accounts were online, yes.

Received dropdown message when trying to send that says:

1. Cannot send message using the sever [email protected]

When checking this window, account I was using to send mail shows this: Account from the list: [email protected](Offline)

Don't know why it says Offline or how to get it to Online.

Checked Connection Doctor: MobileMe; Connection and login to server succeeded.

Account Info: Description [email protected], Server Name: smtp..me.com:x_xxxxx_xxxxx

Cannot send message using the server [email protected]:
The server"smtp..me.com:x_xxxxx_xxxxx cannot be contacted on the default ports.

Account information Advanced.

Use default ports (25, 465, 587)
check mark on: Use Secure Sockets Layer (SSL)
Authentication: Password
User Name: [email protected]
Password: ..........

Macbook Pro
OS X 10.6.8
Mail: Version 4.5

Thanks again for your help.

I've been doing searches here and other places and not found anything that address my particular problem.

Is there anyone who can give me some direction and specific ways to fix this.

Thanks very much.