Can’t duplicate WP installation

My Goal: I want to turn a very large, complex WordPress website on my VPS olddomain.com into newdomain.com.

My Procedure: I installed a new WordPress website at newdomain.com, downloaded all files via ftp from the olddomain.com directory, adjusted the information for database etc. in config.php and uploaded all files again under the newdomain.com directory.

At the same time I exported the sql file of the old database to PHPMyAdmin and replaced the character string olddomain.com in all records with newdomain.com with an editor and imported it into the database of newdomain.com.

I thought this would work, but I get the following error message:

Fatal error: Uncaught Error: Call to undefined function wp_unregister_GLOBALS() in /www/wwwroot/public_html/newdomain.com/wp-settings.php:70 Stack trace: #0 /www/wwwroot/public_html/newdomain.com/wp-config.php(94): require_once() #1 /www/wwwroot/public_html/newdomain.com/wp-load.php(37): require_once('/www/wwwroot/pu...') #2 /www/wwwroot/public_html/newdomain.com/wp-blog-header.php(13): require_once('/www/wwwroot/pu...') #3 /www/wwwroot/public_html/newdomain.com/index.php(17): require('/www/wwwroot/pu...') #4 {main} thrown in /www/wwwroot/public_html/newdomain.com/wp-settings.php on line 70
There has been a critical error on this website. 

I’m a newbie, so I don’t know: Is the way I tried wrong? Or did I make a mistake somewhere?

?BTW: In line 70 in wp-settings.php I read: // Standardize $_SERVER variables across setups.
wp_fix_server_vars();

• This topic was modified 3 years, 10 months ago by Yui.
• This topic was modified 3 years, 10 months ago by Yui. Reason: please use CODE button for code formatting

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