I've installed Genymotion and VirtualBox on ubuntu 16.04 LTS and everything goes fine. Genymotion works well.
Then I installed Genymotion Android Studio Plugin,but when I clicked 'start', it shows: unable to start VirtualBox
Run Genymotion directly it works well, but Android Studio Plugin goes error,It is not like this: Genymotion error at start 'Unable to load virtualbox',how to fix it?
Watch this,run genymotion directly works well, but run android studio plug it shows: 'unable to start virtualbox.'


If you don't have geni virtual box installed, install it.
Your error says that you don't have your virtual box installed in your PC .
If you have then you have not given the right path click on geni icon and set path of it where You installed
(by default its like /Applications/Genymotion.app).you can read here)
Installing it on your pc won't be enough .You need to apply the plugin in android studio as well.
Go to File>settings >(search for plugins in your left side)>select the option plugin > browse repositories > and install geni plugin and you are good to go!
Restart android studio.
Finally if i missed anything watch this video for full thing
Edit:If your are using a V.Box
Go to Network and Sharing Center > Change adapter settings and enable these:
I think that enabling the second will do the job, but I did the first anyways. read More details --------> Unable to start Genymotion Virtual Device - Virtualbox Host Only Ethernet Adapter Failed to start
Hope it helps.