Problems with windows paths

[Gribouillis]

_tkinter.TclError

Observe that the error doesn't come from Python, it comes from the Tcl/Tk library upon which tkinter is sitting. This library may well accept only valid OS paths.

I'm not in the best position to answer, since I think a very good solution would be to get rid of the Windows OS...

More seriously, using the pathlib library to manipulate paths is a robust solution. Starting with Python 3.6, you can also use os.fspath, for example

import os
from pathlib import Path
filename = Path.cwd() / 'spam.png'
astring = os.fspath(filename) # see if this returns a valid Windows path

In good old python 1, 2, 3, one would have written

import os
astring = os.path.join(os.getcwd(), 'spam.png')