The following problem appears after installing Drupal 9.3.7 using the Softaculous auto installation and entering into the administrator area: The website encountered an unexpected error. Please try again later. The following error is logged...
First go into your application folder and check the following files:
Drupal 8 & Drupal 9
grep VERSION core/lib/Drupal.php
grep VERSION includes/bootstrap.inc
Drupal 6 and older
grep VERSION modules/system/system.module