Cannot install Blender 2.93 addons on Windows. Python error

Question

I am having trouble migrating from Blender 2.92 to 2.93. Half of my addons will not install and they are officially supported on 2.93. When I install them, I get an error when I attempt to activate them. The thing is, this is only happening on Windows. I managed to successfully install all of my Addons on MacOS without any issues. I am an artist, not a programmer. Any ideas on what is going on are much appreciated!

The error below is from Botaniq (latest version and 2.93 supported). But the exact same message shows up for all the others.

    Traceback (most recent call last):
  File "C:\Users\GABRIEL\AppData\Roaming\Blender Foundation\Blender\2.93\scripts\addons\botaniq_full\__init__.py", line 30, in <module>
    from . import polygoniq_lib
  File "C:\Users\GABRIEL\AppData\Roaming\Blender Foundation\Blender\2.93\scripts\addons\botaniq_full\polygoniq_lib\__init__.py", line 9, in <module>
    from . import telemetry_module as telemetry_native_module
  File "C:\Users\GABRIEL\AppData\Roaming\Blender Foundation\Blender\2.93\scripts\addons\botaniq_full\polygoniq_lib\telemetry_module.py", line 9, in <module>
    import multiprocessing
  File "D:\Steam\steamapps\common\Blender\2.93\python\lib\multiprocessing\__init__.py", line 16, in <module>
    from . import context
  File "D:\Steam\steamapps\common\Blender\2.93\python\lib\multiprocessing\context.py", line 6, in <module>
    from . import reduction
  File "D:\Steam\steamapps\common\Blender\2.93\python\lib\multiprocessing\reduction.py", line 16, in <module>
    import socket
  File "D:\Steam\steamapps\common\Blender\2.93\python\lib\socket.py", line 51, in <module>
    import _socket
ImportError: Module use of python38.dll conflicts with this version of Python.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "D:\Steam\steamapps\common\Blender\2.93\scripts\modules\addon_utils.py", line 351, in enable
    mod = __import__(module_name)
  File "C:\Users\GABRIEL\AppData\Roaming\Blender Foundation\Blender\2.93\scripts\addons\botaniq_full\__init__.py", line 32, in <module>
    import polygoniq_lib
ModuleNotFoundError: No module named 'polygoniq_lib'

Answer 1

The problem was being caused by residual settings from other software installations I no longer have installed, which made use of Python38, the same one being referenced in the error message in Blender.

Step-by-Step:

1. Go to Control Panel

2. Use the search bar to search for "environment", then click on "edit environment variable for you account".

3. In the window that opened, search the top list for items pointing to python that seem related to your problem. If they relate to programs you no longer have installed, it is probably safe to delete them.

4. Restart the PC and the issue should be solved. That's what solved it for me.

WARNING: Messing with Windows variables is risky if you don't know what you're doing. If you are uncertain of what to do, best to ask someone knowledgeable for help.