Hi @Janus,
In Old version before update ceryficate it'OK
If you have updated the certificate, its thumbprint (in this case the old thumbprint is CE1F23873453D9F733AD24D7DA7BBD83C275CDB4) will change and you need to bind the certificate with new thumbprint to the IIS, POP, IMAP services.
If the renewed certificate has been imported to your Exchange server, please bind it to port 443 (Default Web Site) and port 444 (Exchange Back End) in IIS.
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