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Exchange 2019 SMTP Help

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Exchange 2019 with Outlook 2021 and Windows 11

Brandon Hoskins 0

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?

Thanks

Brandon