Exchange 2016: Problem with SMTP connection on port 587 (and with SSL and TLS security) after install new certificate

Question

_{Thursday, July 23, 2020 6:29 AM}

Hi,

I install new certificate (the same SAN as previous) enable it for pop, imap, iss and smtp but programs which connect to server by SMTP port 587 can connect.

I 've check IIS site and setup new certificate for all two sites on exchange. OWA, ECP works ok, outlook have connections with server too.

In log I see that it is look like user login aor password is wrong but is ok. So problem with process of autentication?

If I restore the old everything start working. Whe could be the problem.

Thenk for help!

Kind Regards Tomasz

All replies (3)

_{Thursday, July 23, 2020 6:43 AM ✅Answered}

Hi,

Have you checked the TLSCertificateName value on the Receive connector which has port 587?

Get-ReceiveConnector "ServerName\Client Frontend Servername" | select Identity,*Tls*

Get the thumbprint using the below command,

Get-ExchangeCertificate

Run the below command,

$cert = Get-ExchangeCertificate -Thumbprint "retrieved from above command"

Set the certificate thumbprint to the TLsCertificateName,

$tlscertificatename = "<i>$($cert.Issuer)<s>$($cert.Subject)"

Set the receive connector,

Set-ReceiveConnector "ServerName\Client Frontend Servername" -TlsCertificateName $tlscertificatename

How to Configure Exchange Server 2016 for SMTP Application Relay

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Thanks,
Ashok M My blog
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_{Thursday, July 23, 2020 7:31 AM}

Great!
Thank you very much for help.
You saved my life!

Very strange behavior of Exchange. First time I see that problem.
Perhaps it is a problem with CU17 to Exchange 2016.

Kind regards!!!

_{Thursday, July 23, 2020 7:41 AM}

Glad to hear that the issue has been resolved and the provided suggestion was helpful.

Thanks,
Ashok M My blog
________________________________________________________________
Please mark the reply as an answer if you find it is helpful :-)
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