SSL error when setting up an Exchange Federation Trust

Question

We are trying to setup an Exchange Federation Trust with our parent compnay.

After opening the firewall holes, the source Federation Trust domain is getting an error when trying to connect.

The user on the source Federation trust is presented with the SSL cert for the Exchange server when trying to browse free/busy calenders.

I am thinking this is because the SSL cert presented is for the local Exchange server itself and not the autodiscover/external mail domain name.

I can edit the IIS edit bindings section on the Exchange server websites but need clarification if this the right solution.

Will assigning the external SSL cert to the Exchange IIS Backend or default website resolve the issue ?

We cannot try the edit bindings without a change control as Production emails will be affected so need to run this after hours.

Answer 1

@ahmed jehanzeb
The certificate that used for Federation Trust are different from the certificate that binding in IIS. It is a separate certificate which only used for Federation Trust don't need assigned IIS services.

The certificate that binding in IIS is used for service which based on IIS, such as OWA, ECP etc. This certificate need contain the domain name and FQDN of your organization in it(Such domain.name, FQDN like: mail.domain.com/autodiscover.domain.com, it decided by which URL that you used to access OWA)

Here is the detailed information about the certificate that used for Federation Trust: Use the Shell to create and configure a federation trust

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