$ drush
Fatal error: Uncaught Error: Class 'Drush\Config\Environment' not found in D:\wamp64\www\workbench8\vendor\drush\drush\drush.php:62
Stack trace:
#0 D:\wamp64\www\workbench8\vendor\drush\drush\drush(4): require()
#1 {main}
thrown in D:\wamp64\www\workbench8\vendor\drush\drush\drush.php on line 62
----------------
$ composer require drush/drush
Using version ^10.1 for drush/drush
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Package operations: 28 installs, 0 updates, 0 removals
- Installing webmozart/assert (1.6.0): Loading from cache
- Installing webmozart/path-util (2.3.0): Loading from cache
- Installing webflo/drupal-finder (1.2.0): Loading from cache
- Installing symfony/polyfill-php72 (v1.13.1): Downloading (100%)
- Installing symfony/var-dumper (v4.4.1): Downloading (100%)
Skipped installation of bin Resources/bin/var-dump-server for package symfony/var-dumper: name conflicts with an existing file
- Installing symfony/finder (v4.4.1): Downloading (100%)
Cleaning: symfony/finder
- Installing jakub-onderka/php-console-color (v0.2): Loading from cache
- Installing jakub-onderka/php-console-highlighter (v0.4): Loading from cache
- Installing nikic/php-parser (v4.3.0): Loading from cache
Skipped installation of bin bin/php-parse for package nikic/php-parser: name conflicts with an existing file
- Installing dnoegel/php-xdg-base-dir (v0.1.1): Loading from cache
- Installing psy/psysh (v0.9.12): Loading from cache
Skipped installation of bin bin/psysh for package psy/psysh: name conflicts with an existing file
- Installing container-interop/container-interop (1.2.0): Loading from cache
Installation failed, reverting ./composer.json to its original content.
[ErrorException]
proc_open(): CreateProcess failed, error code - 5
require [--dev] [--prefer-source] [--prefer-dist] [--no-progress] [--no-suggest] [--no-update] [--no-scripts] [--update-no-dev] [--update-with-dependencies] [--update-with-all-dependencies] [--ignore-platform-reqs] [--prefer-stable] [--prefer-lowest] [--sort-packages] [-o|--optimize-autoloader] [-a|--classmap-authoritative] [--apcu-autoloader] [--] [
]...