Can anyone tell me what causes this error every time I launch an application from the command line?

GnomeUI-WARNING **: While connecting to session manager:
Authentication Rejected, reason : None of the authentication protocols specified are supported and host-based authentication failed.

This one showed up when I typed: gedit

Should I be concerned?

Thanks!

My guess is that you used the console to run gedit, probably to edit one of your /etc files.

Yes, you should be concerned, but only a little bit. Basically, if gedit still works as planned, it's warning you that anybody with "wheel" (su) authority (or something similar) can edit those files. Worse, there's nothing stopping someone from making edits to your config if this happens.

In reality, it's one of those things nobody worries about. If you're the US ARMY, the NSA, etc., you'll already have this shut down. To shut this off in a basic install would mean that you'd need to train everybody to bypass this in order to use the various control panels and GUIs.

To shut this down across the board would likely shut down all installs of anything that starts from the console, but actually installs via GUI. Mozilla might be one, Star/OpenOffice another, and a whole host of GUI config items would be disabled. It's a weakness, but only barely. The biggest threat is from a user, who normally wouldn't want to compromise themselves in the process.

Correct! gedit was started from a console and it ran normally. Thanks for the info and insight!

I got the same warning when i tried to run nautilus from the command line, i logged in as root through su, and tried it, is there any way to open a browser minus the warning...

warning i am getting:
(nautilus:3341): GnomeUI-WARNING **: While connecting to session manager:
Authentication Rejected, reason : None of the authentication protocols specified are supported and host-based authentication failed.

Thanks in advance

why do you need to open nautilus as root?

i got some pdf's in my root, and i don't know how to open them on command line. So i tried to open the browser and the then open it when i got the warning, but why the question?

why are there pdf's in your root directory, sounds kinda odd to me
generally there is no reason to run a a graphical file manager as root
you can just run a pdf reader from the command line as root like
su
kpdf(replace with your pdf reader) <filename>

Okays... that does the work. Thanks for the solution.

I get essentially the same message when trying to start firestarter (firewall configuration tool) as root from the command line. I can run it from the applications menu, but would like to understand why Fedora 10 forbids command line execution. (I've tried it after using both su and ssh to get root access to the shell.) Seems peculiar, to say the least, to force root from command line use.

Thanks for any insights.