Office 365 Migration | Unable to create endpoint | Unable to connect to remote server

I recently was running through an Office 365 Migration (Staged) where I was trying to create the Migration Endpoint.  As I was going through the configuration I was getting the following error message:

After manually typing in the details, I got the following message:

This one was a tricky one as I was running the test through the 'Test Exchange Connectivity' website, and it was all passing without issues.  So it wasn't an autodiscover issue from what I could see. 

After looking into this one for a few hours and not being able to find what the issue could be, I came across an issue with the Autodiscover and IPv6.  When I was on the on-prem exchange server and I tried to ping the FQDN, it resolved an IPv6 address, even though this was disabled on the NIC.

To get around this, I had to edit the Hosts file on the server itself to resolve the IPv4 address when I pinged the server name, and hte FQDN.  After doing this, when I went through the process to create the new migration point, I was able to get past this point and it discovered the server details automatically. 

Winthrop Australia can help you migrate to Office 365 and other IT Support needs in the Perth area.