Update from C2.1 to C4.1

Best to start with a fresh install of CI4 and migrate your site's functionality across.

https://codeigniter.com/user_guide/insta...e_4xx.html

CodeIgniter 4 is a rewrite of the framework and is not backwards compatible. It is more appropriate to think of converting your app, rather than upgrading it. Once you have done that, upgrading from one version of CodeIgniter 4 to the next will be straightforward.

Thank you for your reply.

But since I'm going from version CI2 to version CI4 directly, that's not going to be a problem?
The link talks about updating version CI3 to CI4, not version CI2 to CI4