Script @php artisan package:discover handling the post-autoload-dump event returned with error code 255

Question

I moved my project from desk to another.
When I run php artisan it does not work.

I tried to run composer update, but it returns the

Answer 1

If this happened after Laravel update from 6.x to 7.x, then this could be due to the update of Symfony. See the upgrade guide of this part: https://laravel.com/docs/7.x/upgrade#symfony-5-related-upgrades