I spent most of last weekend fighting with my 7550 to get BT programming to work.
Here's what I had to do.
First, uninstall and reinstall your PC's bluetooth drivers. Make sure they are up to date.
you have to setup your radio as a BT PAN (personal area network) device to be able to read/write to it. In Windows 7, if you see it in your device list, you should be able to click on it and connect as a PAN, if your drivers are working correctly. If it tries to use a PIN, most likely Windows 7 will try to send an 8 digit PIN, which you cannot enter all 8 digits.
IGNORE this, let it fail, Windows will figure out it cannot pair this way. It will allow you to pair with the radio without one. IF YOUR PAIRING IS SUCCESSFUL, your PC will show up in the radio's BT device list, and upon a successful PAN connection, you'll hear a high pitched chirp come out of your radio.
YOU'RE GOOD TO GO at this point.
You will have to manually connect to your radio EACH TIME you want to read or write from it once you've successfully set the radio up as a PAN device by going to your network places in Windows, clicking on the radio, selecting PAN connection.
IF YOU CANNOT get your radio to respond (chirp) after pairing the BT side of things, try uninstalling/reinstalling your BT drivers.
This is how I got BT reading/writing to work on my XPR7550 using 3 different Windows 7 machines, two are running 32 bit, one 64 bit. Two different BT adapters too.
Hope this helps.
