I’ve encountered this problem with the Hydrogen package since I updated atom and its packages a couple days ago, not having changed anything since the last time it worked.
It appears to find the kernel for Python 3 - Hydrogen kernels updated: Python 3.
At first it didn’t seem to work for neither Script nor Hydrogen packages, but after adding another line to the PATH variable, the Script package seems to be able to run the code.
I’m using Anaconda’s version 3.6.5 of Python.
I’ve tried uninstalling Anaconda and installing Python 3 alone, but it didn’t work. I have also reinstalled Anaconda completely, aswell as Atom (but for some reason it remembered the packages I had installed with their respective configurations, so maybe it wasn’t a complete uninstallation).
Atom : 1.30.0 Electron: 2.0.5 Chrome : 61.0.3163.100 Node : 8.9.3
Note that I’ve searched over a whole variety of other posts but either I didn’t understand what they were saying (I’m quite new to programming), they weren’t exactly alike, or their solutions were already applied to my problem.