My Phone Says NR & Has No Dial Tone

Your phone shows NR and/or loses registration periodically. Often a reboot resolves the problem for a while.

Symptoms

Please note: This guide assumes that you have been able to make and receive calls using this phone for a while. If this is a first time installation there may be other issues; please consult the user manual or email support.

Common Mistakes

1. Unless you are using the Voipfone Virtual PBX, two phones cannot be simultaneously registered on one account. They will cause random un-registration
2. Another thing to check quickly is that registration expiry is set to 60 seconds; many phones are set at 3600 seconds as default

On Rant

Unlike some other VoIP companies, we run an open network and allow our customers to bring their own SIP based hardware to connect with us and try to provide support for it no matter how awful some of it is. As a consequence we get blamed for all sorts of NR problems; almost always they are down to poor phones or firmware, incorrect configurations, bad internet connections or local router and LAN issues. It is not beyond possibility that our network is at fault but if it is we will have thousands of telephones suffering not just yours - so blame us last!

Off Rant.

Check Your Telephone

Power down your phone and your router. Check the Ethernet cable is properly plugged into both the phone and the router, then reboot them; router first. Keep your eye on the phone for an hour or two, sometimes this is enough to clear the problem.

Update Your Firmware

Make sure you have the most up to date firmware for both your router and your phone. (Netgear routers in particular originally shipped with some problematic firmware and see Grandstream below).

Get Your Configuration Right

To work properly on our network your telephone or adapter must use our optimal settings. You will find many of these for the most popular devices along with set-up wizards on our website under support.

If your phone is not listed there, you will need to use the general phone configs.

Known Problems

Grandstreams are very cheap and popular phones. Unfortunately, the firmware has known problems which cause them to un-register.

They have issued a new firmware for the GXP2000 to solve this which you can find on the grandstream website.

Snoms are the most reliable phones we know but there is an issue with their v5 firmware. We ship our Snoms 3x0 with v4.5 PLEASE DO NOT UPDATE IT. Not only will it cause the phone to regularly go NR, it requires a fiddly TFTP process to reset it. (The most stable firmware for the Snom 190 is v3.60x).

[edit: 22/06/06. The new Snom 300 ships with v6 firmware and is stable. We are still testing the v6 for other 3xx devices].

[edit#2 26/10/2006 v6xx of all snom software is now tested and works well].

If you do need to downgrade please follow the instructions found on the snom website.

Check also that your 'proposed expiry time' is set to 60 seconds and that, if 'support broken expiry' is not greyed out, that it is set to 'on' (both under Line 1, SIP tab). Under the Advanced line in the yellow side bar, confirm that 'Challenge Response on Phone' is set to Off.

Draytek 2600V routers are SIP aware but they often cause us problems. If you use this router and are experiencing NR please check for firmware updates. At the time of writing, they also require a TFTP procedure to set registry expiry time to 60 seconds.

They occasionally do strange things with DNS. A power down and reboot often resolves this.

Asterisk & Asterisk@Home users can find set up details here.

We've recently seen a user solve an unregistering problem by adding

RTPkeepalive=60

in sip.conf

If other efforts fail - a total fix is to ask us for IP registration - email support with your details.