Windows Live Mail can’t email out- stays in outbox

I have windows 7 64. I am using Microsoft Security Essentials.

And Malwarebytes was added about a month ago.

But since I loaded windows live mail into this new system back in May 2013... I can only email out on the default email account.

The four other email accounts can't send out mail.

ATT gave me their webpage help...but was no help.

Where do you think my problem is?

I have checked it all with a fine tooth comb.

All email properties settings seem correct.

Helpless Glen Jameson