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Here's a list of possible problems and their solutions that might arise using the virtual machine.
64-bit guest OS list is not displayed
VirtualBox does not present the list of 64 bit OS when creating the virtual machine.
This might be because your own computer is only 32bit. In which case you can't use the virtual machines.
If you have a 64bit computer, this might be because of settings in Windows 8 or 10 that conflict. Please see this article for more information on the resolution: http://www.fixedbyvonnie.com/2014/11/virtualbox-showing-32-bit-guest-versions-64-bit-host-os/#.VvvZBT_VmuA
VT-x is disabled in BIOS
Some users may get this error when first trying to run the virtual machine (or a similar error):
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Mac users. The above instructions apply to machines running Windows/Linux which allow access to the BIOS. On Macs, this is not possible though this issue can still occur. If you see this message on a Mac, it's likely that another application has changed the state of the VT-x hardware acceleration. In which case, a reboot of the machine usually clears it.
If none of the above solve the problem, make sure you are running the latest version of VirtualBox for your machine. Older versions of VirtualBox do not support VT-x on newer computers.
Drag'n'Drop not working
Check that the Settings for the VM are set to 'Bidirectional'. Also, when the VM is running, check that the menu option "Devices" -> "Drag'n'Drop" is also set to Bidirectional.
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