1. Genymotion Desktop in a Virtual Machine
This error can happen if you try to run Genymotion Desktop in a virtual machine. Running Genymotion Desktop in a virtual machine is not supported. See Can Genymotion Desktop run in a virtual machine?
2. Hyper-V (Windows) and VPN
This can mean that a VPN and/or Hyper-V is interfering with VirtualBox.
To fix it, please refer to:
3. Firewall
Firewalls may disrupt the connection between Genymotion player and VirtualBox host-only interface. If you use a firewall, make sure that it does not block your local network (typically, 192.168.0.0/16). For more information, please refer to Genymotion Desktop and firewalls
4. SSSE3
If none of the above apply to you and you can still launch Android 6.0 and below, then your CPU may not support SSSE3.
Important
Android 7.0 and above require specific SSSE3 instructions, if your CPU does not support SSSE3, your computer will not be able to run virtual devices with Android 7.0 or above. To verify whether your CPU supports SSSE3, please refer to https://en.wikipedia.org/wiki/SSSE3#CPUs_with_SSSE3
5. Laptops and Notebooks
This error can be caused because VirtualBox took too long to allocate an IP to the device. On Laptops and Notebooks, this may happen if you are in "save battery" power mode. To avoid this, make sure to set your power mode to "performance".
Please note that VirtualBox is CPU intensive when emulating Android OS, and may drain your battery. We recommend plugging your power cord when using Genymotion on a Laptop or Notebook.
6. Low-end hardware
This error can happen on hardware which does not meet Genymotion requirements. Please refer to Genymotion Desktop - Hardware requirements.