I have an acer laptop and I installed Windows xp sp2.
I want to find Bluetooth stack name in my laptop (ie)
WIDCOMM/Microsoft Bluetooth stack.
Check "Add/Remove Programs".
Open Device Manager (
If you see a category "Bluetooth Radios" and under it a "Microsoft Bluetooth Enumerator", it's Microsoft's stack.
If you see "Bluetooth Devices" without the "Enumerator", it's Widcomm.
Note: Windows Update can remove the Widcomm stack and install Microsoft, if you download the Bluetooth update.
Speaking of Windows Update... Using XP without SP3 is not the best idea.