Failure
Error: Failed opening required ' root-dir ...is the directory, where your Drupal website files and folders are stored (core, modules, sites, themes, .htaccess etc.), if you follow the recommended project structure it's the web folder of your project directory, i.e. /var/www/html/wisski.com/web, or C:/xampp/htdocs/wisski.com/web. \modules\contrib\wisski\wisski_adapter_sparql11_pb\src\Plugin\wisski_salz\Engine/../../../../..//vendor/autoload.php' (include_path=' project-dir ... if you follow the recommended project structure, this the top level directory of you Drupal instance, containing the web and vendor folder and the composer.json, i.e /var/www/html/wisski.com/ or C:\xampp\htdocs\wisski.com\. Project directory and root directory (where your website with the index.html lives) can be the same. \vendor/pear/archive_tar; project-dir ... if you follow the recommended project structure, this the top level directory of you Drupal instance, containing the web and vendor folder and the composer.json, i.e /var/www/html/wisski.com/ or C:\xampp\htdocs\wisski.com\. Project directory and root directory (where your website with the index.html lives) can be the same. \vendor/pear/console_getopt; project-dir ... if you follow the recommended project structure, this the top level directory of you Drupal instance, containing the web and vendor folder and the composer.json, i.e /var/www/html/wisski.com/ or C:\xampp\htdocs\wisski.com\. Project directory and root directory (where your website with the index.html lives) can be the same. \vendor/pear/pear-core-minimal/src; project-dir ... if you follow the recommended project structure, this the top level directory of you Drupal instance, containing the web and vendor folder and the composer.json, i.e /var/www/html/wisski.com/ or C:\xampp\htdocs\wisski.com\. Project directory and root directory (where your website with the index.html lives) can be the same. \vendor/pear/pear_exception; project-dir ... if you follow the recommended project structure, this the top level directory of you Drupal instance, containing the web and vendor folder and the composer.json, i.e /var/www/html/wisski.com/ or C:\xampp\htdocs\wisski.com\. Project directory and root directory (where your website with the index.html lives) can be the same. \php\PEAR') in include() (line 10 of $ root-dir ...is the directory, where your Drupal website files and folders are stored (core, modules, sites, themes, .htaccess etc.), if you follow the recommended project structure it's the web folder of your project directory, i.e. /var/www/html/wisski.com/web, or C:/xampp/htdocs/wisski.com/web. \modules\contrib\wisski\wisski_adapter_sparql11_pb\src\Plugin\wisski_salz\Engine\Sparql11EngineWithPB.php)
Solution
Navigate to your WissKI module directory, i. e. $ root-dir ...is the directory, where your Drupal website files and folders are stored (core, modules, sites, themes, .htaccess etc.), if you follow the recommended project structure it's the web folder of your project directory, i.e. /var/www/html/wisski.com/web, or C:/xampp/htdocs/wisski.com/web. /modules/contrib/wisski and start composer update with
composer update