According this answer in How do I delete a folder which is nested quite deep and avoid “File name too long”?, I created 1.bat file with following source:
@echo off
if not (%1)==() cd %1
for /D %%i in (*) do if not %%i==_ ren "%%i" _
pushd _
%0
popd
I put this file near the folder which I want to delete.

I click on 1.bat
and see following:
.....
Access is denied.
The system cannot find the path specified.
Access is denied.
The system cannot find the path specified.
Access is denied.
The system cannot find the path specified.
Access is denied.
The system cannot find the path specified.
Access is denied.
The system cannot find the path specified.
Access is denied.
....
What do I wrong?