Windows

If you have a Bluetooth device which is not supported directly in Windows XP and which was not designed explicitly for Windows XP with Service Pack 2 (SP2) then you are likely having problems. One such is the ISSC IS1002N "Horus" bluetooth module, one of the smallest bluetooth reference designs around and thus a fairly popular candidate for super-cheap bluetooth dongles.

Unfortunately, installing a unit based on the reference design (and driver) results in a failure to install the Microsoft bluetooth stack, and necessitating the use of a third-party stack. This is a highly unsatisfactory solution as many third-party stacks will not work properly with third-party applications. A little creative googling allowed me to find a working solution.