Can't install High Sierra on VirtualBox or Parallels-not solved by changing date I'm trying to install High Sierra on VirtualBox or Parallels Desktop. My host is MacOS Sierra.

My installer is 10.13.6 Build 17G85 with its checksums verified.

I created the ISO with this method:
Install macOS High Sierra as VirtualBox guest (on macOS High Sierra)?

Both VirtualBox and Parallels boot up the ISO to the "Install MacOS", but when I hit 'Continue', I'm having the "This copy of the Install MacOS Sierra application is damaged, and can't be used to install MacOS".

Changing the date with the terminal using "date 090100002018" (1st of Sept.2018) doesn't work.

Any ideas?
It appears my installer .app REALLY got damaged.
(maybe becauseI moved it around unzipped through my networks?)

A fresh .app download from Apple solved my problem.

I was so used to it being a signed code problem 
solved by changing the date that I went there too fast.

Sorry for the noise.