Let’s suppose you want to go there : https://SERVER_URL/space/YOUR_SPACE/Files
The first problem is that instead of prompting your the login/password to enter, it’s redirecting you to the login page which does not seem necessary because in the URL you are already asking for a specific space. So in this case you don’t need to be redirected to the login page. You would like to see the login/password popup directly (if no token available) and be redirected automatically to : https://SERVER_URL/ExternalAuth/Windows?requestToken=XXX&space=YOUR_SPACE&returnUrl=%2Fspace%2FYOUR_SPACE%2Ffiles
So now you are unfortunately in the login page. Click on login => you are NOT redirected to the Files tab but to the default tab which is tasks. Here is the URL of the login button : https://SERVER_URL/ExternalAuth/Windows?requestToken=XXX&space=YOUR_SPACE&returnUrl=%2Fspace%2FYOUR_SPACE%2Ffiles
The URL seems good but it’s like the “returnUrl” parameter is not taken into account.
Thanks