Thread:Project:Support desk/Can't upgrade (xampp)/reply (7)

I think the problem is the way how PHP is accessed. When you call a file with the web browser, one version of PHP may be invoked, while when you call a file from the shell, another version may be used.

Since you say that your wiki is basically working (not now, but before you upgraded MediaWiki), I guess that the PHP version, which is used when you hit a page with the browser, is fine. update.php however uses the shell, which might be a completely different version.

On the shell, please type this command

php -i

This will (among other things) display a list of the loaded extensions. Look there to see if mysql or mysqli are installed!