How to install php_wincache extension for php 7.1 on Windows?

Question

I've followed all instructions from this tutorial wincache installition

but at the end I've got an error:

Unable to load dynamic library 'C:\dev\7.1\php\ext\php_wincache.dll' 

What can be the problem? php_wincache.dll exists in the needed folder, but can'be be found by php.