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Exchange 2019 SMTP Help
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Exchange 2019 with Outlook 2021 and Windows 11
Good Afternoon All,
I have a new Exchange 2019 install and have installed my certificate I got from an external CA. I can get POP3 to work for incoming mail and outgoing SMTP when using STARTTLS but I want to use SSL/TLS for the SMTP. However, when I select with port 587 or 465 I get the following error:
Send test email message: Your server does not support the connection encryption type you have specified. Try changing the encryption method. Contact your mail server administrator or Internet service provider (ISP) for additional assistance.
I have confirmed that my client machine of Windows 11 is using TLS 1.2 and Exchange 2019 is using TLS 1.2 as well. Does anyone know how to fix this?