Yesterday we upgraded one of our apps from 10.6.10 to 10.12.5, since the upgrade our External Database Connector (EDC) no longer connects, if I run the query via the code it pulls back the tables and results as expected, running in the app takes a long time then errors as below, The TCP/IP connection to the host (sqlserver) (instance), port (number) has failed. Error: "(Server\Instance). Verify the connection properties. Make sure that an instance of SQL Server is running on the host and accepting TCP/IP connections at the port. Make sure that TCP connections to the port are not blocked by a firewall.". If we use a laptop that still has 10.6.10 it works fine, our DBA has checked and cant see the actual connection even being attempted in the SQL logs.