Xlib: Invalid MIT-MAGIC-COOKIE-1 key

[mzilikazi]

I am attempting to use the knx-installer on a Kanotix remaster. Not only that but I've also nuked all of KDE. Instead I wish to use GDM. The installation actually works fine and from run level 3 user can issue startxfce4 and away it goes and works like a dream. If however one attempts to use ANY login manager including kdm, gdm or xdm I get the dreaded Xlib: Invalid MIT-MAGIC-COOKIE-1 key in .xsession-errors. I don't *think* it's an installer issue but rather .Xauthority but then again if I were sure I would fix it right? Anyway...I don't know too much about how the xserver permissions work. Thanks for any ideas.

[Markus]

Have you tried just deleting/renaming ~.Xauthority and restarting X.