Creating new user breaks login

After creating a new user, attempts to login fails with 500 Internal server Error (“Uh oh, It’s broken”). It seems to authenticate ok but fails on browsing the site, i.e. the error occurs on the “…/s/dashboard”. I can login with the original user, and everything works, only additional users fail. New user is also Administrator. (mautic 2.1.1)

After creating a new user, attempts to login fails with 500 Internal server Error (“Uh oh, It’s broken”). It seems to authenticate ok but fails on browsing the site, i.e. the error occurs on the “…/s/dashboard”. I can login with the original user, and everything works, only additional users fail. New user is also Administrator. (mautic 2.1.1)