Hi @Paul Kraemer ,
Agree with Andy, please first check if that's your issue as the article mentioned above.
If that's not your case, considering it's the first time to configure your accounts in this PC, we could temporarily exclude the interfernce of some corrupted data files. As I know, the setting of "My outgoing server(SMTP) requires authentication" may also affect the issue, and the password prompt may happen when you haven't configure your account appropriately(In general, we need to check this option), it's suggested to check and change your setting to see if the issue has any difference(Control Panel>Mails>Email Accounts>double-click your account>More settings>Outgoing server).
Hope that would be helpful to you, and if your issue has any update, please feel free to post back.
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