I use your library to interface with our Bluetooth activity monitor. Our customers generally use Microsoft Stack. Occasionally, on some PCs I get error 10050, when connecting to the device. I can discover ok, and do service discovery ok but when connecting to the Serial Port service this error is thrown. This only affects a handful of PCs and it works succesfully on hundreds of others.
I have tried to reproduce the error on our own machines but failed every time. This generally happens on CSR or Broadcom dongles with MS stack.
Had it most recently on a Sony Vaio, with Vista and Alps Broadcom 2046 internal adapter. MS Stack version 188.8.131.5201.
I ran Find and Connect and modified to show the whole exception stack:
Failed to connect remote service  Franson.BlueToolsException: Failed to connect remote Bluetooth service
at Franson.BlueTools.Toolkit.PullExceptions(IntPtr obj)
at Franson.BlueTools.ServiceStream..ctor(IntPtr nativeProvider)
at FindAndConnect.MainForm.serviceList_SelectedIndexChanged(Object sender, EventArgs e)
Hope this is informative and helps to find a resolution.[:)]