In some instances TCP is better to use for remote connections to Advantage.
UDP is very limited and if you have a very locked down environment this can be the reason why UDP does not work.
In general using TCP is more reliable since both the client and the server acknowledge communication between each other. While UDP does not, it only sends information between client and server without confirmation.
In a very locked down environment with firewalls in between the client computers and the serve using UDP is very limited, so by forcing the use of TCP this will allow you to connect