Hi @Paul Durand
Welcome to our forum!
According to your description, it seems that your Outlook client is unable to add email accounts. Since your email account is provided by a third party.
It is recommended that you first try to check whether you can log in properly through the web version. Then make sure the configuration is correct when adding it to the Outlook desktop client. (Port Configuration Information & App Password)
If the problem persists, try the following possible workarounds:
Change the setting from IMAP to POP.
Re-download the classic version of Outlook. You can't open classic Outlook on a new Windows PC - Microsoft Support
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