WireShark not capturing data for every request

Hi,

We have installed WireShark version 1.6.4 and WinPcap version 4.1.2. We have installed a service on port 9081 and configured WireShark to include port 9081 in Edit -> Preferences -> Protocols -> HTTP -> included 9081 for text box field for ‘TCP Ports’. We provide options in Capture -> Options -> Provide ‘host ip address’ in Capture Filter-> and click on ‘Start’ and WireShark starts running. When we execute a request which uses service configured on port 9081, we expect certain lines in data captured from WireShark. Like if we put ‘http.request.uri contains “PrintServer”’ in Filter text box and click on ‘Apply’, we expect to see some lines. Our issue is that we do not see these lines every time we execute a request which uses service configured on port 9081. We see those lines randomly. Are we missing anyting? Can any one of you please help us with this?

Thanks,
Shilpa