Remote server ignors TcpClient connection

Remote server ignors TcpClient connection

I have a Windows Mobile 6.5 app that has been communicating with a test
server in my home for months just fine. I have moved my server software to
a new PC hosted remotely (I connect to it via remote Desktop Connection).
My app uses TcpClient tcpclnt = new TcpClient(theIP, thePort); to connect
to the server. When theIP is set to my home server, everything works fine.
When it is set to the remote server running the exact same software, my
app throws A connection attempt failed because the connected party did not
properly respond after a period of time.
I wrote a c# windows form application and used the same code block as a
test. I can connect to both servers with no problem calling from a
desktop. I can invoke responses from my remote server program calling the
IP and port from other utilities and even as the URL x.x.x.x:port in a
browser. But the remote server completely ignores any connection attempt
from the WM6.5 application - even though the exact same application
connects to my home server if I change only the IP address in the
TcpClient connection.
My home server is a Windows7 Pro SP1 and the remote is Windows Server 2008
R2 SP1.
What could possibly be the issue establishing a connection with the WS2008
server?