Codeigniter: URI you submitted has disallowed characters

Question

My URL is:

https://example.com/c3dlZXRfcmFqdmk5MUBob3RtYWlsLmNvbQ= 

When I remove = then it works fine.

I have this in config.php

$config['permitted_uri_chars'] = 'a-z 0-9~%.:_\-'; 

Error:

The URI you submitted has disallowed characters. 

How can I allow = or == signs in URI?

I have tried it by changing this:

$config['permitted_uri_chars'] = 'a-z 0-9~%.:_\-='; // added = sign at the end 

Answer 1

In /project-folder-name/application/config/config.php configure this variable:

$config['permitted_uri_chars'] = 'a-z 0-9~%.:_\-@\='; 

it also works for @ character