He was receiving the following error message.
Autodiscover was not configured for external use. So we had to configure that, by using the following commands. $env:computername is a system variable, which calls the computer name you're running on the command on. Feel free to change this to the CAS server name.
I always use autodiscover A record for this, but this requires you to have it on the certificate as a SAN or use a wildcard cert. Feel free to change this to whatever is on the certificate you're using. If you're using a self signed certificate....replace it with one from a recognized CA.
Set-AutodsicoverVirtualDirectory -Identity "$env:computername\Autodiscover (Default Web Site)" -ExternalURL "https://autodiscover.domain.com/Autodiscover/Autodiscover.xml"
Set-ActiveSyncVirtualDirectory -Identity "$env:computername\Microsoft-Server-ActiveSync" -ExternalURL "https://autodiscover.domain.com/Microsoft-Server-ActiveSync"We also set up a CNAME for autodiscover address to go to the A record for the server externally.
Once we had completed this, we ran the Exchange Connectivity Test, which returned the following result.
Further troubleshooting resulted in the following webpage, when attempting to get to the address specified in the commands above.
Heading into IIS Manager, we headed straight for the Authentication for the Autodiscover web page.
We noticed that Windows Authentication was set to Disabled. Setting that to Enabled, we were still out of luck.
We then double checked the Microsoft-Server-ActiveSync Authentication, and Windows Authentication was Disabled there, too.
Changing that we managed to get some success!
This resulted in a successful Autodiscover test.
However, \when attempting to run through the Migration Endpoint Wizard, it returned the following error.Everything was correctly configured.
Ultimately the last piece of the puzzle was IPv6.
It was disabled on the host, but still communicating, and taking priority for autodiscover.
Setting a couple of static addresses in the HOSTS file, allowed us to connect instantly.