I downloaded the files and placed them in a folder and then added the location to the system PATH. Ran the flash again but got the same result. It says flashing successful but the Core starts flashing green then every 30 seconds or so it flashes white once and then restarts flashing green.
My wifi router is set WPA/WPA2 - Personal.
Iām running out of ideas now - maybe time to get in contact with @corey or hello[at]particle[dot]io
Thanks, @ScruffR I will do that. All this time I thought I was talking to a Particle representative! 
No sorry, Elites are only enthusiastic volunteers 
I wonder if this gives any indication of what the problem is:
This does not necessarily mean anything. On my Windows 8.1 & Windows 10 machines I never get a WiFi network when scanning via CLI but when I enter my known credentials my devices still connect without fuss.
It worked! It finally worked! I followed the instructions in this post:
Replacing "Spark" with "Particle". Step 6 did not work (see screen shot above) so I applied the wifi settings using Putty. Later I applied different wifi settings using the Android App and it worked too.
@ScruffR , I know that most of the steps in this post were suggested by you and I had tried them, but I guess it was just a matter of doing them in the right sequence. Or maybe I was flashing the wrong cc3000. Anyway, thanks for your help and patience!
Glad to hear that it finally worked out for you 
It can't connect to WiFi channels >11, so set up your router accordingly.
Thanks @ScruffR, I have been battling the eternal green blink on the Core for so long and almost gave up, untill I read your post. My wifi was on channel 13! Fixed it and the Core is completely back alive.
Thatās the beauty of this community: Collective memory 
But the docs would also have stated the fact
https://docs.particle.io/support/troubleshooting/common-issues/core/#device-doctor
https://docs.particle.io/guide/getting-started/start/core/#what-39-s-on-it-