I got a few complaints from my end users that his/her Cisco 7921 IP Phones suddenly stopped working.
After some troubleshooting I found out that the phone lost its IP configuration settings.
After configuring the right settings, everything worked again...but after a random period of time, the configuration is gone again.
According to the users the phone was not low on battery and has not been turned off.
Does somebody have any idea what might be wrong?
Thanks in advance.