add a user to a specific group

This will be the solution of the following error message when the external usb device is attached on the Linux.

Error org.freedesktop.DBus.Error.AccessDenied.



type groups in the xterminal,

userid audio video

where userid is your user id.


As root
usermod -a -G cdrom userid
usermod -a -G plugdev userid
usermod -a -G powerdev userid

reference http://forums.debian.net/viewtopic.php?p=209366&sid=e101ea755847bc7f4cd84db9c0b033f8