When i look into settings bluetooth is not turing on
and i also tried this command as root/etc/init.d/bluetooth start but still its not working.
Please Help Me!
Your Bluetooth dongle may require special drivers to use it. Also, it may not be compatible with Linux entirely.
First, we need to know the brand and model of your bluetooth dongle, in order to help you further.
its CSR 4.0 Bluetooth Dongle.
From the information I was able to gather, those bluetooth chips do not support Linux. Listed OS support Windows 10, 8.1 / 8, 7, Vista, XP.
My recommendation for a Bluetooth Adapter That Supports Linux
Hello, I have been having this problem for about a year. I also use a dongle usb and I was never able to make it work. Detail, in addition to the Zorin OS I use Windows dual boot on the same PC, and on windows everything works ok. I don't know what else to do, I also want help!
There are a few requirements in getting Bluetooth working. But the main one that is the most important, is that the bluetooth dongle supports Linux, thats your starting point.
The next thing you gotta do, is make sure your Linux OS, has all necessary Bluetooth Libraries. Yes, Windows comes with all that stuff by default usually.
But many Linux OS's are trimmed down versions, which have missing libraries. Those must all be installed. The other thing, is its best to have Kernal version 4.9 or better.
And if your running on Zorin OS 15.3, which is based off of Ubuntu 18.04, you should be running kernal version 4.9 at the very least already! And the kernal can always be upgraded to a higher version as well.
Once the requirements are met, the dongles should work perfectly. The link that I provided to the dongle that supports Linux, descusses these things in the description of the product. 
In case the link dies some time in the future, here is the contents carbon copied (well, fixed a few minor typos), thanks to Sujeet Buddiga, the original author. Note that in 3) and on, you will have to use the proper string (brcm/xxx.hcd) you found in 2) to get the right result.
dmesg | grep brcm
Thanks for this great write up 
Do you think you can make a Tutorial with it?
I am sure many members will be benefited from it.
Hello everyone, I strongly suggest this tutorial. it works for me ..
