When trying to start the debugger in SQL Server Management Studio, I received the error: Unable to start T-SQL Debugging. Could not attach to SQL Server process on ‘%dbservername%’. Click Help for more information.
Configure the database engine service with a Domain user account, or more specifically, an account that can be authenticated from the machine that is running Management Studio. I noticed in a Wireshark trace on my pc that a NTLM call was being made with the account of the database engine service.