CI4 Manual Installation

I don't use Windows.

The problem is the installation is forced to use an optional PHP International local language settings library. 

Solution is to either install the library or modify the following file:

Code:

File: ./system/CodeIgniter/CodeIgniter.php
    /**
   * Handles some basic app and environment setup.
*/
    public function initialize()
    {
    // Set default locale on the server
    // John ADDED FOLLOWING CHECK BECAUSE STILL TO BE SET ON MY SYSTEM 
            if( function_exists('locale_set_default' ) ) :    
           locale_set_default($this->config->defaultLocale ?? 'en');
    endif;

I will try this on a new machine and will post back here. On the current machine it is working by using Composer and moving forward with building Startup application.