NETGEAR ReadyNAS connection failed AFP

We have a ReadynNAS 1100 (File server) in the office. For some reason the AFP service stopped working. The service was on, but OS X couldn't connect. The solution was to re-install the ReadyNAS firmware. After re-install we only needed to change the admin password and change the IP-address. All other options, data and add-ons were still there.

ReadyNAS User Guide