Exchange 2010 server unable to join the DAG

Issue: Exchange 2010 server unable to join the DAG

Cause: IPV6 wasn't fully disabled via registry. Also, DNS was configured for the replication NIC

Resolution: Disable DNS configuration for replication NIC so that it doesn't register in AD DNS. Properly disable IPV6 in the registry by doing this:

Launch Regedit.exe

o Go to HKLM\System\CurrentControlSet\Services\TCPIP6\Parameters and Create a new DWORD value named DisabledComponents

o Edit DisabledComponents to have a Decimal Value of 4294967295

Reboot the server. When the server comes up, try adding the server to the DAG