Error 404 - page not found

Hi !
I don't know where the issue is comming from but I am trying to deploy the solution and it can't seem to work.
I followed every step in [this doc](https://techcommunity.microsoft.com/t5/security-compliance-and-identity/host-dke-on-iis-using-an-on-premises-server/ba-p/1811046) and the official one (modifying the settings file, DNS registration, etc.) but when I try to run the test script I get the following error : Validation failure: Unable to access the provided url.

My webserver is working correctly, I can access the default page from another computer and I tried to put the publish folder in the default site and it's still not working. If I try to browse the DKE website, I get a 404 error.

I don't know if it's linked but, it said that https://login.microsoftonline.com/common/v2.0 should be reachable but it is not (I tried it on mulptiple device it never works - error 404).

As anyone else encountered this issue and can help please ?