Just a quick note to remind myself how I fixed the problem installing VirtualBox 5.2.10 on a Mac laptop running 10.13.4.
The installation seemed to go well until it reached the end and reported failing to install. I’ve had this issues for a few weeks already and Google for solution seems to have hit and missed until today. I finally found a solution posted here: https://github.com/docksal/docksal/issues/417.
Basically, I need to go the System Preferences and tick the box to allow ‘System software from developer “Oracle America, Inc.” was block from loading’.