Can't auth from domain to ISPConfig panel

Hi,
I met a strange problem while setting up a new ISPConfig server (I follow this guide: https://www.howtoforge.com/tutorial...-9-stretch-apache-bind-dovecot-ispconfig-3-1/): When I try to login to the admin panel from the IP address directly, authentification is ok but when I want to access the panel from a domain, the auth info box is present but authentification fails every time I try to login (I already try to change the admin password). I checked the logs but I found nothing relevant.
I search in all ways but I didn't find, so if anybody has an idea...
Thank you.

 

hmm usually it's the other way round that using ip doesn't work. Usually it is a cookie issue. have you tried different browsers / deleting cookies for that domain?

 

Wow, impressive, it was actually a cookie problem, I would never have done the relation!
Thank you very much!