If you are using a VPN, stop your VPN or refer to the article Genymotion Desktop and VPN.
Hardware virtualisation feature is disabled
Make sure that the Intel VT-X, AMD-V or SVM virtualization feature is enabled in your BIOS. Please refer to "Your CPU is incompatible with virtualization technologies" error for more details.
Please refer to "Unable to start the virtual device" (Windows 10)
If none of the above worked for you, try to re-install VirtualBox and Genymotion (See How to uninstall Genymotion Desktop completely (purge)?)