When things go wrong with your apps, looking through your log files is the first step to troubleshooting your problems.
The most common logs to examine are your app's Nginx, Apache, and PHP logs, which will likely show details about any errors:
Nginx Access Log
/srv/users/sellcloud/log/APP/APP_nginx.access.log
Nginx Error Log
/srv/users/sellcloud/log/APP/APP_nginx.error.log
Apache Access Log
/srv/users/sellcloud/log/APP/APP_apache.access.log
Apache Error Log
/srv/users/sellcloud/log/APP/APP_apache.error.log
PHP Access Log
/srv/users/sellcloud/log/APP/APP_phpX.Y.access.log
PHP Error Log
/srv/users/sellcloud/log/APP/APP_phpX.Y.error.log
Remember APP is the name of your app and X.Y is your app's PHP version.
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