Sure that it didn't update? You can check the Operating System version at System->System info->Summary: Operating System ... Version: ...
I assume you are talking about a windows network. Try rebooting your pc and they probably will appear again. Important is that Samba is activated on the devices. You could also try to access to a single device through the windows explorer with \\device-name or \\device-ip.
I'm at work now, I'll check when I get home in 4hrs
Thanks for the tip, I managed to connect with \\device-name from work and if I look in the update folder, the .zip file is still there, should it be gone if it updated normally ?