Comment 7 for bug 22948

(In reply to comment #6)
> Message is
> ---
> Linux Kernel
>
> User interaction required! A new version of the Linux kernel has just been
> installed. We strongly recommend that your machine is restarted as soon as
> possible to complete the system update.
> ---
>
> Closing it makes it go away, until you reboot again.
>
> I queried dpkg, here's the result:
> update-notifie 0.40.12
>
> Do you want the whole xsession errors log, or are there particular lines (a grep
> query e.g.) you would be interested in?

Your complete .xsession file please. And the output of:
$ ls -alR /var/lib/update-notifier/user.d
and your ~/.update-notifier/hooks_seen file as well.

Do you use anything "unusual" on your system? E.g. a uncommon filesystem?
Problems with the clock maybe?

Could you please please check the updated version in
http://people.ubuntu.com/~mvo/update-notifier/?