We are finally looking to migrate from Exchange 2010 to 365, it’s a small number of users so I’m looking to complete this over a weekend with a cutover migration.
I have tried to add a migration endpoint in Exchange Online which fails and refers to https://testconnectivity.microsoft.com/
When I run the Exchange Server Outlook Connectivity test, these are the results, do I need to add a rule to TMG?
Our Set up
Microsoft Forefront Threat Management Gateway 2010 (Server 2008 R2)
Exchange 2010 Mailbox server (Server 2008 R2)
Exchange 2010 – Hut Transport + CAS (Server 2008 R2)
Using Lets Encrypt SSL Certificate