Ahh!! I understand what you're getting at now!! (Only took half a day & a sledgehammer

)
OK - I've looked through my registry & found LOADS of entries for 'Bluetooth' & a couple for the Stowaway Keyboard that I use. Having seen what's in there I must salute you for your bravery, as I would not like to attempt to change any or all of the entries - there's a lot of them, which means there's a lot that can go wrong.
So yes, there must be a way to reset bluetooth back to base levels, but it needs a man with a stout heart (I would also suggest that he has a friend that can sit down next to him him so that they can compare all the different bluetooth entries in each other's registry & decide which ones they want to change).