How to Install Virtualbox on Windows 10 host?

You can install VirtualBox 4 on Windows 10 (Note it doesn't work for the new VB 5) by disabling Bridge Networking during the installation. To be more precise I succeeded with VirtualBox-4.3.28-100309-Win.exe installed under Windows 10 x64 Build 10074 with no bridge networking.

Latest version of Windows 10 seems to allow installation of both VirtualBox 4 and VirtualBox 5. Still I found some issues initializing the network adapter through Vagrant.

There is a VB defect ticket here related https://www.virtualbox.org/ticket/14040 . If the network adapter cannot be properly initialized use the following executable https://www.virtualbox.org/attachment/ticket/14040/VBox-Win10-fix-14040.exe. You have to run it as administrator during the VM startup after which it work properly.