Kevin,
Could you please confirm that you were using an address that includes actual machine name, and not localhost? Localhost is a hostname for the loopback IP address of 127.0.0.1, which eventually points to the device itself, and not the PC where UltiDev Cassini is hosted.
Assuming you used actual hostname of the machine running Cassini and your web server, we are very surprised to hear that PocketPC 4.2 seems to be failing to connect to the TCP/IP on another Windows. From what you describe PPC 5.0 seems to make a difference, but we never heard about 4.2 having issues with TCP/IP connectivity. Frankly, we are at loss as to which part of the system to blame: Cassini, PC or PPC.
Best regards,
UltiDev Team.
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