TCP/IP Zerowindow

Hi I have a rather complex Solution I have been working with. It�s basically a server and client, that receives commands form remote controller application. It appears to work fine and with different windows OS using C# code bases on the Windows Boxes. My problem is when I send a Command the Rabbit 4000 series controller coded with Dynamic C 10.45, using the co_exec.lib a lot stabile I might add. Receives the command and Sends back and acknowledge packet back to the Windows box. Everything looks to have worked now open threads or sockets. Till I look on WireShark. Then I see a bunch of commands coming out of the TCPIP Stack in the Rabbit to the windows box, with Zerowindow tags on them. When I trace the code I see nothing to indicate I have a socket open on windows box or rabbit core (WiFi 4100 Core). I am thinking I am missing something simple in the TCP Protocol or something I need to turn off? Any ideas?

I have attached the trace from WireShark In a zip file.