Problem with IMAP after renewing SSL certificate


Hello Everyone
I have 2 CAS servers and 2 MBX servers , after renewing the expired SSL certificate on both of CAS , i had a problem with users who use protocol IMAP to connect , applications who send mails via IMAP and MAC users .
I found this errors with the following ID in booth of my CAS servers :
Schannel errors with s ID : 36888 , 36874 , 36887

I followed the link bellow and created the messing values :

The problem remains the same ,
Would you help me please identify the problem71533-error.png

I have also found the following error :46 = TLS1_ALERT_CERTIFICATE_UNKNOWN

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  1. Xzsssss 8,861 Reputation points Microsoft Vendor

    Hi @Anonymous ,

    Good day!

    Sorry but i can't understand the logs, if you could, please translate it into English. And share the General of these three (36888 , 36874 , 36887) events.
    Only users using IMAP got this error? And what's the symptoms, like users couldn't login or something else?
    And the application is a mobile app?
    Forgive me about these stupid questions, and please share more details with me so i can better understand this issue and help you...

    I think you can first check the IMAP settings with:

    Get-ImapSettings | Format-List *ConnectionSettings,*Bindings,X509CertificateName  

    Make sure the certificate is right.

    As for the error: 46 = TLS1_ALERT_CERTIFICATE_UNKNOWN
    Since it's saying this error is a Certificate error, you can check the Bindings in IIS. Make sure the Https sites are using the correct cert.


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