A network-specific error occurs in MAGE logs after starting the Unified Mail Sync agent service. The following will possibly be present in the MAGE.log:
2015-10-15 14:06:23.0609 Px954 Tx6 A- C- M- Trace SQL server binding information: 'Data Source=MIGCONSOLE\QMMINSTANCE;Initial Catalog=MMEXProject;Integrated Security=False;User ID=sa;Password=********;Connect Timeout=180'.
2015-10-15 14:06:23.0609 Px954 Tx6 A- C- M- Info A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 28 - Server doesn't support requested protocol) at Quest.MigrationManager.Exchange.Basis.QSqlCommand.ExecuteReader()
The agent log panel may also not be visible in the console, and the "open log" option when right clicking on the agent may also be greyed out.