Python 2.7.12, 3.4 and 3.5 are installed on my Windows 10 computer. Running a test of tkinter in 2.7 works, but the test in either version of Python 3 throws errors:
in Python run import tkinter;tkinter._test()
_tkinter.TclError: Can't find a usable init.tcl in the following directories:
_tkinter.TclError: Can't find a usable tk.tcl in the following directories:
Searching on the errors, there were several references environment variables TK_LIBRARY and TCL_LIBRARY,
set TCL_LIBRARY=C:\Python3\tcl\tcl8.6
set TK_LIBRARY=C:\Python3\tcl\tk8.6
The solution most often found was to copy the contents of the Python3/tcl/ folder to the Python3/Lib folder, but that seems to pollute the Lib folder.
My solution is to create symbolic links in the Lib folder:
as administrator open a console window:
mklink /J c:\Python3\Lib\tcl8.6 c:\Python3\tcl\tcl8.6
mklink /J c:\Python3\Lib\tk8.6 c:\Python3\tcl\tk8.6
So far, this has worked. There are many other folders in the TCL directory, so additional links may be needed.