Now that the September 2021 Cumulative Updates (CUs) for Exchange Server 2019 and Exchange Server 2016 have been released, customers around the world now have access to a new security feature in Exch...
Updated Oct 01, 2021
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Nino_BilicWe had a similar predicament mentioned by raphG67 (RemoteCertificateValidationCallback certValidationCallback, X509Certificate clientAuthCert, Boolean isResponseJson)
Cert chain validation was failing because of an old gpo (Exch servers were not allowed to reach out...“Allow issuer certificate retrieval during path validation.“ - ...because of reasons...)
Incomplete certificate chain
Cannot find certificate:
CN=Microsoft RSA TLS CA 02, O=Microsoft Corporation, C=US
PS: the url that Exch srv should contact is signed by an X509 cert so thats why it failed for us...which is a good thing.
Maybe that will help others.
Curious about the result of feedback you have received and mentioned since it has been almost a month since then....
Thank you.
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