Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires PHP extension ext-xsl * but it is missing from your system. Install or enable PHP's xsl extension. Problem 2 - Root composer.json requires veewee/xml ^2.6 -> satisfiable by veewee/xml[2.6.0, ..., 2.11.0]. - veewee/xml[2.6.0, ..., 2.11.0] require ext-xsl * -> it is missing from your system. Install or enable PHP's xsl extension. To enable extensions, verify that they are enabled in your .ini files: - C:\tools\php\php.ini You can also run `php --ini` in a terminal to see which files are used by PHP in CLI mode. Alternatively, you can run Composer with `--ignore-platform-req=ext-xsl` to temporarily ignore these required extensions.