Minpack2 dll error

“C:\Program Files (x86)\PsychoPy3\pythonw.exe” “C:\Program Files (x86)\PsychoPy3\Lib\site-packages\psychopy\app\psychopyApp.py”

does not produce any output at all.

in trying to find the cause, I have started python and ran this
from psychopy.app._psychopyApp import PsychoPyApp

which generated a buch of errors leading to this one:

from scipy.optimize import minpack2
Traceback (most recent call last):
File “”, line 1, in
File “C:\Program Files (x86)\PsychoPy3\lib\site-packages\scipy\optimize__init
__.py”, line 386, in
from .optimize import *
File “C:\Program Files (x86)\PsychoPy3\lib\site-packages\scipy\optimize\optimi
ze.py”, line 37, in
from .linesearch import (line_search_wolfe1, line_search_wolfe2,
File “C:\Program Files (x86)\PsychoPy3\lib\site-packages\scipy\optimize\linese
arch.py”, line 18, in
from scipy.optimize import minpack2
ImportError: DLL load failed: %1 is not a valid Win32 application.

any advice?

StandalonePsychoPy3_PY2-3.2.4-win32.exe installs and works correctly
StandalonePsychoPy3-2020.2.5-win32.exe installs but does not run at all.

Thus, maybe there are some dependency issues? Some libraries should be installed to make 2020.2.5 run?