For Outlook.com accounts, mail server is type HTTP and not POP3. Delete the account from live mail, and put it back in again. When putting it back in again, manually configure server and change POP3 to HTTP.
I've created an outlook address ie JohnDoe@outlook.com and added it to the windows live mail program. I can receive mail at that address, but can't send any mail from that address using windows live mail. It's the same for any outlook.com address. Using outgoing server port 25. Also tried ports 465, and 587 with no luck.

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