Comment 14 for bug 1059600

@Stinger: Yes, you could use sessioninstaller again, when Sebastian has fixed the bug ;-) And he's right, there is no point in cluttering this report.
Can you please file a new bug against the "packagekit" package about the "GDBus.Error:org.gtk.GDBus.UnmappedGError.Quark._pk_5ftransaction_5ferror.Code4: SimulateInstallFiles not supported by backend" issue? Because while the first one was a sessioninstaller issue, the second one is from PackageKit. Oh, and it's probably not even a bug...
Run "sudo apt-get install gdebi-core" and try again, it should work then ;-)