I have found it I think.
Error 8 is when the main program detects that it is being started from the old original pscan.eu pscanloader program. It attempts to upgrade it to the pscan.uk one and if it fails it do this then you get Error 8.
Figuring out
why this is failing won't be easy, however there is a solution that you can do yourself.
I am guessing that you originally installed pscan into something like c:\pscan.eu.
My suggestion is to make a completely new folder called c:\pscan.uk and put a completely new pscanloader.exe from the new pscan.uk website and just start again. Essentially you start again as if you are new customer and follow these instructions
http://pscan.uk/install/windows.html
Once it is working just delete the old installation.
I am afraid that this mess is because the old program would look on the pscan.eu website when you run it to check for updates and we have been informed by the European Commission that we could loose our .eu domain anytime after brexit. Therefore I started up pscan.uk which required a new auto update mechanism, and therefore a new pscanloader program ahead of time so that as many of the old pscanloader programs would update as possible before falling off of the edge of the Internet (well maybe the Dover cliffs).
Read about that here
https://www.theregister.co.uk/2018/03/29/eu_dumps_300000_ukowned_domains_into_brexit_bin/
Unfortunately there must be a bug or some unexpected scenario in there. It worked for me in the lab but maybe your laptop is built differently, or maybe you originally saved pscanloader as admin or read only or some other scenario that my program doesn't detect.