bhatta, You can click the link below to watch the youtube video that shows a possible resolution for getting your Bluetooth working. [URL]
Hello All, Recently I upgraded to Windows 10 64 bit on my Dell Vostro laptop. After update, Bluetooth adapter has gone missing from the device manager. I have the old drivers from win 7, but these are not running as the message says "this app cannot run" or things to that effect. I tried to install the Lenovo drivers as suggested, but that is not successful as it asks me to uninstall the existing bluetooth drivers. For the life of me I cant find these anywhere. Any suggestions? 
Bluetooth adapter missing after upgrade to windows 10