I can open a device

[da]

When I want to open a device, so as a pendrive, has a message that was not possible to mount the file system, even though I am administrator. In addition, the computer is not shutting down, only back to the login page. It started happening today (15º september). Sorry for my English.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: nautilus 1:3.1.90-0ubuntu3
ProcVersionSignature: Ubuntu 3.0.0-11.18-generic 3.0.4
Uname: Linux 3.0.0-11-generic i686
ApportVersion: 1.23-0ubuntu1
Architecture: i386
Date: Thu Sep 15 14:39:25 2011
ExecutablePath: /usr/bin/nautilus
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Beta i386 (20110901)
ProcEnviron:
 LANGUAGE=pt_BR:pt:en
 PATH=(custom, no user)
 LANG=pt_BR.UTF-8
 SHELL=/bin/bash
SourcePackage: nautilus
UpgradeStatus: No upgrade log present (probably fresh install)
usr_lib_nautilus:
 deja-dup 19.91-0ubuntu3
 evince 3.1.90.1-0ubuntu1
 file-roller 3.1.91-0ubuntu1
 gnome-disk-utility 3.0.2-1ubuntu2
 nautilus-share 0.7.3-1