How to resolve deprecated property issue on IIS Server?

I'm encountering an issue while hosting a CodeIgniter project on an IIS Server. Instead of the default controller, I'm receiving the following error message:

A PHP Error was encountered
Severity: 8192

Message: Creation of dynamic property CI_URI::$config is deprecated

Filename: core/URI.php

Line Number: 101

Backtrace:

File: C:\inetpub\wwwroot\app\index.php
Line: 315
Function: require_once

Despite setting up the web.config file, HTTP mappings, ISAPI, URL rewrite module, and FastCGI, the problem persists. I'm seeking assistance in resolving this issue as I'm currently unable to proceed.