Geobar
OK, try this.
Go to Tools/Accounts, select your email account. Cllcik Properties/Server Tab.
Look in the 2 boxes named:
Incoming Mail (POP3)
Outgoing Mail (SMTP)
Do these 2 boxes have the same address in them?
If they do, click the Settings Button in that window.
In the Settings options, place a check mark in the "Use same settings as my incoming mail server" option.
Click OK / Apply / OK.
Close and reopen Windows Mail and try again.
If this post helps to resolve your issue, click the Mark as Answer button at the top right of this message.
This will help others who are having this issue find the answer quicker.
Ronnie Vernon
Microsoft MVP
Windows Desktop Experience