I had to install Assistant 2 on my desktop, trying to revive what appears to be a bricked Spark.
Windows sees the SD card in the Spark, and the contents on it, but the DJI Assistant app just sits at the startup screen, oblivious to the fact that the Spark has been plugged in.
And yes, I've tried multiple USB cables.

In the Devices listing, under "Other Devices" DJI shows with a "Driver Error" notation.
When installing the Assistant program, there was no indication of any problem with the installation.
Yes, I was logged in as Adminstrator, and I right-clicked and installed Assistant as an Administrator.

Installed without issue for me on Windows 10

I remember that there was an issue with Windows 10 when I installed it on my PC, but to be honest I forgot the details. After all I got it working. I believe to recall that I had to tell Windows to accept installing/using a driver from unknown origin or something similar. Check your Windows security settings if you can find any options of that kind.

Please try to change a PC to reinstall the DJI Assistant 2 and see if it works. And you can follow the idea above. Thanks for your help.