Drag and drop doesn't work between host and VirtualBox on Windows 7

Open windows explorer as administrator and drag from there:

• open Windows directory
• Locate explorer.exe
• Right click, run as administrator

Tested on 5.1.8, host and guest both windows 7 x64, using guest additions.

Note: You might need to shutdown and start again the guest os, at least for me the guest bugs badly when I try to drag a file from a non UAC explorer window.