Fix Uncaught Error: Class InitParamListener Not Found After Upgrading to Magento 2.4.x

The InitParamListener error occurs when upgrading to Magento 2.4.x due to class path changes.

What Causes This Error?

This error typically occurs when:

• Custom modules reference the old class path
• Extensions haven't been updated for Magento 2.4.x compatibility
• Autoloader cache needs clearing

How to Fix the Error

Follow these solutions:

• Clear generated files and cache `rm -rf var/cache var/generation var/page_cache`
• Recompile Magento code `bin/magento setup:di:compile`

- Update all extensions to Magento 2.4.x compatible versions - Check for hardcoded class references in custom modules

• Run setup upgrade `bin/magento setup:upgrade`

Wrap Up

This error is usually resolved by clearing cache and ensuring all extensions are compatible with your Magento version.