Solution for Windows Server Event ID 15021 – HttpEvent error occurred while using SSL configuration for endpoint 0.0.0.0:444.

Czech: Během používání konfigurace protokolu SSL pro koncový bod 0.0.0.0:444 došlo k chybě. Stavový kód chyby je obsažen ve vrácených datech.

This error message usually appears when sysadmin change certificates for services like IIS or MS Exchange. Problem is between SNPP and HTTPS service  communication which is broken. To fix this problem you should check your installed certificates and apply correct Thumbprint to each service.

Fix:

cmd
netsh http show sslcert

SSL Certificate bindings:
-------------------------

    IP:port                      : 0.0.0.0:443
    Certificate Hash             : 123456abcd
    Application ID               : {4dc3e181-e14b-4a21-b022-59fc669b0900}

    IP:port                      : 0.0.0.0:444
    Certificate Hash             : xyz7890
    Application ID               : {4dc3e181-e14b-4a21-b022-59fc669b0900}

You can see different Certificate Hash on 443 and 444 service. Lookup your newly installed certificate thumbprint and set it for 0.0.0.0:444 service. In this example we need to repair 0.0.0.0:444 from xyz7890 (old cert. thumbprint) to 123456abcd.

Note – replace Certificate Hash and Application ID with your values.

netsh http delete sslcert ipport=0.0.0.0:444
netsh http add sslcert ipport=0.0.0.0:444 certhash=123456abcd appid="{4dc3e181-e14b-4a21-b022-59fc669b0900}"

Reboot your server.

Now you should see no more Event ID 15021 errors and MS Exchange should work without problems.