Error while updating new version: CDbConnection failed

[dev]

CDbException
CDbConnection failed to open the DB connection.

I checked main-custom.php file was missing, added the old page with db credentials.

I created a file main-custom.php in apps/common/main-custom.php, added the credentials and checked the url, it's a blank page now. Snapshot http://prntscr.com/d3pfes

please suggest to fix the issue.

 

[twisted1919]

I will close this since if you follow the upgrade steps from https://kb.mailwizz.com/articles/upgrade-steps/ the update will work just fine.