My story so far to repairing bluetooth and activesync when they absolutely refuse to play ball...
(1) Disabled Microsoft ActiveSync to stop my mobile synchronising every time I wanted to charge it.
(2) Updated all software via Windows Update, including Bluetooth drivers.
(1) ActiveSync refused to work again, even with repeated un-installs and re-installs.
(2) My ePox BT-DG03 Bluetooth USB Dongle stopped working because the latest Microsoft Bluetooth drivers are now called ABE Bluetooth Controller and don't work with it (these replaced the previous Windows XP SP2 bluetooth drivers "Generic Bluetooth Radio" and "Microsoft Bluetooth Enumerator".)
(1) Took a complete, clean copy of my C:\Windows\Inf, C:\Windows\System32 and all sub-folders onto my iPod and brought them in.
(2) Uninstalled ActiveSync and all associated Bluetooth drivers (Add/Remove Programs and Device Manager.)
(3) Connected Device via USB cable; Machine should recognise Generic RNDIS device and ask for drivers, etc.
(4) PLugged-in bluetooth dongle; Machine should again recognise bluetooth device and ask for drivers, etc.
When drivers are asked for;
(1) Un-install all the existing device drivers to avoid conflicts.
(2) From device manager, perform Update Drivers.
(3) Select "Install from a list or specific location (Advanced)."
(4) Select "Don't search. I will choose the driver to install."
(5) Click "Have disc".
(6) Browse to your backed-up copy of C:\Windows\Inf and select the file "drvindex.inf".
(7) From then on it should find the correct devices and all you have to do is show it where to find the right files.
I had to do this 2 or 3 times before the driver installs stuck, but now it's fairly happy and I can just plug the dongle and mobile phone in and no more reinstalls need to take place.
The key files I found are:
(1) rfcomm.sys (system32\drivers)
(2) wshBth.dll (system32)
(3) irftp.exe (system32)
(4) irmon.dll (system32)
Standard Modem over Bluetooth link;
(1) bthmodem.sys (system32\drivers)
Be warned, there are more files the auto-installer will ask for, but if/when I need to do this again, I'll try and note them all down.
(1) I've had one instance where the bluetooth dongle needed to be reinstalled, but with care and forethought, the right drivers can be picked - this is down to selecting Show All Devices (when the option is presented) and always selecting \Inf\drvindex.inf, to give the auto-install the best chance of finding the right driver.