What I have done is modified the Bluetooth driver file that comes with XP SP2, to include this dongle by adding its hardware ID to the supported devices list.
Before you can install this, you must make sure you have updated your XP to at least Service Pack 2, as this included the Bluetooth Support Addon.
Extract files somewhere like the desktop
Plug USB Bluetooth Dongle in
XP wont find drivers automatically, direct it to the folder where you extracted the files
If a question about installing the drivers, continue anyway
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