Failed unmount

[Zaki Akhmad]

Hello,

I can't copy files to my flashdisk. Whenever I copied files, suddenly
the files was missing from the flash disk (when I re-insert the
flashdisk).

When I tried to do the umount from terminal, it shows like this:
<blockquote>
za at zara:~$ umount /media/2348-7FF0
Unmount failed: Did not receive a reply. Possible causes include: the
remote application did not send a reply, the message bus security
policy blocked the reply, the reply timeout expired, or the network
connection was broken.
</blockquote>

Someone could help me? I am using kubuntu 11.10

-- 
Zaki Akhmad