some hotmail.com email address showing invalid certicate if sending from Mac mail app

fairwindw1 wrote:

I recently have a wired email issue with Mac Mail App.

I have an email address say, if I use this email in Mac Mail to send , the recipient side outlook will show invalid certificate.

But if I sent email using this address from web or outlook for Mac , no such issue.

I also have another email address say , doesn't have such issue.

contacted Microsoft email team, they blame Mac mail app since it works fine on the web or outlook for Mac.

what could go wrong?

I tried to remove and add back the email account , no fix

OS Monterey , Mac mail version 16.0

[Email Edited by Moderator]

If Mail on your Mac can't verify a server's certificate

Sign or encrypt emails in Mail on Mac - Apple Support

Use SSL to connect to the outgoing mail server in Mail on Mac

The current stable release of Monterey including bug fixes, is macOS 12.5.1

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