I have upgraded my moodle from 3.5 to 3.8 and went through all the necessary versions of PHP and MySQL required. There wasn't any hick ups in the process of upgrading however the dropdown list of countries in location setting does not work. I checked the moodle/lang/en and countires.php file and everything is fine.
Due to this issue, I could not register my site. Please Help!
Thank you.