On Windows 10, you might find that after installing Xamarin tools and the Xamarin Android Player you can’t launch the simulator from Visual Studio nor the Xamarin Device Manager with the error ‘VBoxManage command failed. See log for further details‘.
XAP is automating VirtualBox in the background, but you’ll probably find that you can’t manually start the VM image from there either, but with a more helpful error ‘Failed to open/create the internal network‘ and ‘Failed to attach the network LUN (VERR_INTNET_FLT_IF_NOT_FOUND)‘:
The fix is to edit the connection properties of the VirtualBox Host-Only network adapter (as named in the error message) and make sure that VirtualBox NDIS6 Bridged Networking Driver is ticked. In the example below, even though the installation appeared to go swimmingly it didn’t enable the bridge driver.
Tick the box and off you go!