- Pinging by PC name from the PCS7 Engineering Server was resolving to the address on the office network, not that of the terminal network.
- The Engineering Server LHMOSTS file had the client PC with the terminal network address
- ipconfig /flushdns did not fix the problem
After some googling I stumbled on the solution - the hosts file! It seems that lmhosts and hosts are used by different utilites and ping is one of the utilites that uses hosts.
After adding the correct name and ip address to hosts ping resolved to the desired address and PCS7 downloaded the OS client project without errors. This would indicate that PCS7 also uses hosts or at least the tcp/ip utilies like ping that reference it.