Sorry to warm up this topic again, but I’m also still facing the same problem. 
I already tried the registry hint of whitfieldp, but unfortunately, this didn’t help anything.
So far, I had installed version 1.97.0, but this version has some issues when trying to use generators like Gaussian, as already discussed here:
https://discuss.avogadro.cc/t/trouble-with-generators-in-1-97/4711
Therefore I tried to update to newer Avogadro versions.
But as I found out, no newer Avogadro version works on my system (Win 10 Enterprise 22H2 Build 19045.5608). I installed 1.98.0, 1.98.1, 1.99.0, and 1.100.0.
After trying to start Avogadro, I can see Avogadro2 for a few seconds in the background processes of the task manager, then it vanishes, and no program window ever opens.
Of course, I also tried a complete computer restart after every Avogadro installation, but Avogadro still won’t start.
Both Python and Avogadro were added to the Windows PATH variable.
Curiously enough, when I return to version 1.97.0, the software runs again as expected, but still with the old “Error running script…python313…” issue when using gaussian.
I’d be grateful for any idea, what I could try else.