Running php bin/magento setup:upgrade caused magento 2 app to crash

Question

I originally was facing an issue of not being able to save any configurations on my magento application, and a user on this site recommended to run the php bin/magento setup:upgrade command as the first step to resolving my issue.

Well, that only created a much larger issue. When running the command, I got the following as an error:

Class Magento\Framework\App\Config\FileResolver\Proxy does not exist

Also, now my magento application is completely crashed and I am unable to access it from the browser. When trying to access from the browser (whether it be the admin site or the user facing site), I get the following error:

An error has happened during application run. See exception log for details.

I am really just looking to get my application back up and running. Does anyone know how I can possibly revert the actions of running the upgrade command or somehow restart the application?

UPDATE: If I run the "php bin/magento setup:install" command again, then I get the error

Impossible to process constructor argument Parameter #2 [ <required> Magento\Framework\Mview\ViewFactory $viewFactory ] of Magento\Framework\Mview\TriggerCleaner class

Answer 1

Try the following solution:

Remove the vendor folder and clear composer cache:

rm -rf vendor
composer clear-cache

Then run setup upgrade, re-compile code and deploy static content:

composer install
bin/magento setup:upgrade
bin/magento setup:di:compile
bin/magento setup:static-content:deploy -f

If you see any errors, update it in your question, and I'll help.

• Tu Van: If this answer works as your expected, please mark it as accepted, which indicates your issue is resolved and it makes it easier for others with the same issue to find a verified answer.
• Tu Van: Normally, that solution will resolve your issues and get your application back up and running. In case your application still has other issues and you need to fix them asap, you can hire me as a freelancer, and I can fix your application quickly even though any errors.