Disclaimer: Koga is not a major chipset manufacturer (like Broadcom, Realtek, CSR). It is most likely a rebranding brand (common on Amazon, eBay, AliExpress). Therefore, "drivers" depend entirely on the underlying chipset.
Run the Bluetooth Troubleshooter found in Windows Settings under "Troubleshoot" > "Other troubleshooters". Hardware koga bluetooth dongle driver
Can’t find devices / pair fails
➜ Uninstall driver → disconnect dongle → reboot → reconnect. Disclaimer: Koga is not a major chipset manufacturer
If the device is still not working, use the Microsoft Support Update Utility method: Press Start, type Device Manager, and open it. Expand the Bluetooth section. Plug in the dongle
A "Koga" Bluetooth dongle is often a generic term for various low-cost USB Bluetooth adapters (such as those using
CSR 4.0 Drivers: Many Koga-style dongles use CSR chips. You can find generic CSR Bluetooth Dongle Drivers through hobbyist sites or driver archives