It could be a corrupted driver. First, make sure the Blue Tooth device is discoverable and that the computer is searching for Blue Tooth devices at the same time and then paired if discovery is successful.
The best way to update the driver is to go Device Manager then uninstall the device and check box "Delete Driver" (if shown). The click on the Action tab at top of Device Manager and click on Scan for Hardware changes. This should force the computer to download the current driver.