I am using Ubuntu 11.10 (64 bits) and I do not want to mount automatically USB thumb drives in my system. I tried the command dconf-editor and gconf-editor but there isn't the icon to disable it in nautilus preferences (apps|nautilus|preferences|media_automount).
Thanks.
To disable Nautilus automount use this command in a terminal
gsettings set org.gnome.desktop.media-handling automount false
To enable it again open a terminal and use this command
gsettings set org.gnome.desktop.media-handling automount true
You first need to install dconf editor in Software Center. In my case it shows remove because I have already installed it
Then you need to open dconf editor via Dash
Then goto org.gnome.desktop.media-handling
You will find automount checkbox on right hand side. Uncheck it
Install dconf-tools, and run dconf-editor. Then see in dconf-editor, key
org.gnome.desktop.media-handling/automount
I believe you can find dconf-editor is part of dconf-tools. If you search for dconf, it should show up.
The key is under org. As posted, dig down to org.gnome.desktop.media-handling/automount.
I'm copying Bruno Pereira's edit into its own answer, since because it doesn't involve installing any additional GUI tools, it's probably the most desirable option for most people.
If you prefer not to install anything extra in your system. You can use gsettings to change dconf keys.
To disable Nautilus automount use this command in a terminal
gsettings set org.gnome.desktop.media-handling automount false
To enable it again open a terminal and use this command
gsettings set org.gnome.desktop.media-handling automount true