Hi, I'm new to Boost and am trying to write a command line networking tool. I am currently working in Windows XP SP2 using MS Visual Studio 2005. I use the default compiler. I have read a few tutorials and examples on using Asio, and thus wrote my app using that information, as well as information from the reference library. Currently the problem that I have is that I cannot set the port used by the endpoint to the value I want - 10540 - it is always set to 11035. I'm not sure why this is, I cant find the number 11035 anywhere in the code or documentation so I am not sure where it comes from. I have tried to instantiate a new endpoint using the IPv4 address as a string and the port number as a short, and have also tried to construct a query that specifies the protocol, host name, service name (port number in this case) and the numeric_service flag. In either case, when I debug, the port of the endpoint is always 11035, no matter what I set it to. I am able to connect to the endpoint, but not able to write data to it. I get a "File handle supplied is not valid error message". I presume the most likely reason for this is that the port 11035 is not open. The machine that I am trying to connect to is running Red Hat EL4 Update 4. I would appreciate any help in this matter. Thank you, Jonathan.