In order to install oauth2 server module, I have added oauth2 server library in drupal-8 as instructed in https://www.drupal.org/node/1938218

Now oauth2 library exist in path/to/drupal-8/libraries/oauth2-server-php, but I still get the oauth2 server library unavailable error.


I tried changing libraries folder permission to writable, moving the libraries folder path to sites/all/libraries and sites/default/libraries, without success.