Hi @Sharma, Rohit
Why do I need to renew my "Microsoft Exchange Server Auth Certificate" when I have 3rd party signed cert?
Based on my knowledge, the two certificate have different functions in Exchange Server. The Auth Configuration and Auth Certificate are used by Microsoft Exchange server to enable server-to-server authentication using the Open Authorization (OAuth) protocol standard. The Auth Certificate is also used by several Exchange Server security features.
If you don't renew this certificate, an expired auth certificate will prevent you from accessing ECP and OWA, Outlook clients slow to start and not displaying the user's calendar and so on...
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