I've just started browsing this forum so I don't know if you have a solution for this yet. I have the same ipaq, and have a belkin adapter for my desktop, and had the same problem. I had to make a change in the way windows does bluetooth in order to get it to work, but I don't remember now just what it was. If you don't yet have this fixed, let me know and I'll look back through my notes and tell you what I did and see if it helps you.
Ok, I've had an ipaq 1945 (the one with built in bluetooth) since july. Now in september i got a d-link bluetooth dongle for my pc (which runs xp pro w/ sp2). I put the dongle on the front usb 2.0 ports on my computer. I then set up the software that came with the dongle. After the computer restarted, a big blutooth icon appeared in the system tray. Then, windows did its auto detect thing and installed a bunch of stuff automatically for bluetooth. Then another, smaller, bluetooth icon appeared in the system tray. So now I tried to do all the bluetooth stuff with my pda. So first I went to the bigger blurtooth icon and tried to find my device, but it said no decive could be detected. (btw, the bluetooth was activated on the pda this whole time). Then I tried to use the smaller icon to use blutooth and it detected it right away. However, all I can do then is send files to the device. So what I wanna do is sync with bluetooth using activesync, get internet access, search folders and all that other stuff from the pda.
As well, I tried going by this website's description, but I could finish the last few steps because the big bluetooth icon wasn't detecting the pda.
http://www.logodesignworks.com/iPAQ-activesync-bluetooth-synchronization.htm
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