If you still have the original driver CD or a backup of your Windows 8.1 system, you can extract the isscbta.inf file and force-install it on Windows 10.

ISSCBTA stands for Integrated Silicon Solution, Inc. Bluetooth Controller Driver. It's a Bluetooth driver developed by Integrated Silicon Solution, Inc. (ISS) for their Bluetooth controllers. The ISSCBTA driver is used to facilitate communication between a Bluetooth device and a Windows 10 computer.