We currently use snom 300 VoIP phones here in the office and the other day I was asked to troubleshoot a phone that had all of a sudden stopped working. The error that it was coming up with was NR and every number that you tried to dial would result in a ‘forbidden’ error message showing up on the phone.

Now NR stands for Not Registered in snom language and so logging onto the phone’s web interface configuration utility (simply point your browser to the IP address listed on your phone <- grab it by going to the Information -> IPAdr menu option on the phone), I was able to see from the System Information page that the Identity 1 Status was yielding an authentication error.

The next step was to access the Identity 1 menu option and on loading up the page, I could immediately see that the password field for the Login Information had been cleared, meaning that in order to fix the problem I simply needed to re-enter the secret set on the server for that particular extension.

Easy as pie really.