Comment # 4 on bug 943717 from Krasimir Ivanov

The check shows as follows:
# systemctl status vboxdrv
vboxdrv.service - LSB: VirtualBox Linux module
   Loaded: loaded (/etc/init.d/vboxdrv)
   Active: inactive (dead)

Then I started it from the CLI and then try my virtual machines.
It worked!

Thank you very much for this very useful hint!!!

Now in the Services Manager vboxdrv is marked as active.
But I could not make there active the Voboxadd.

Any way I can do my job with the virtual machines now, so 
THANK YOU VERY MUCH TO YOU for helping me so promptly!