Contact URI showing sip:s@ipaddress

Hi All,

I am currently running FreePBX with Asterisk installed and it has been working fine for quite some time but recently I noticed my inbound calls were failing.

Upon discussing with the service provider they indicated that the Contact URI is in an incorrect format. In the Registration message being sent to to the provider the header for the From and To addresses are fine in the format of

The Contact URI though in which they key on for delivery of calls is showing:

Ex. sip:s@

My trunk settings are (edited):


Register String:

Any idea why the “s@” is showing up and how I can get rid of it / change it? My trunk settings are what I thought would correct it but I can’t seem to get it to work :frowning:


Because that is the default when you don’t specify an extension (it should not normally be a problem, as s is valid as an extension).

Specify an extension in the register:

; Format for the register statement is: ; register => [peer?][transport://]user[@domain][:secret[]]@host[:port][/extension][~expiry]

; If no extension is given, the 's' extension is used. The extension needs to ; be defined in extensions.conf to be able to accept calls from this SIP proxy ; (provider).
or use a callbackextension, instead:

;callbackextension=123 ; Register with this server and require calls coming back to this extension

Documentation quoted from extensions.conf.sample.

Hi David!

Thanks for the prompt reply - much appreciated. I can go in and manually edit the file to do this but I believe the provider is looking not for the extension but the actual DID number in the Contact URI field. Is there a way to insert / override with this instead?

Sorry for what may seem a novice question - I’ve used FreePBX for some time with the underlying Asterisk and it runs quite well but every now and then something like this creeps up and I’m a little novice in the code area.

Thanks so much again for the help!


Either of the two methods described will do that. If your problem is how to get FreePBX to set one of these options, you should ask on

Hi David,

Thanks again for the reply. I have also posted in the FreePBX forum.

If I were to make these modifications I would likely try the first method but which .conf file would I need to edit for this? Is this also in the extensions.conf file? The second one looks to be in the extensions.conf file but I was not sure about the first method?

Thanks again!

They are both in sip.conf.


I have used the /extension to change the contact and it does not take effect. The username/extension I am using is quite long (30 chars) and wonder if that is the problem. I have tried friend and peer, but it never changes.


My Register string looks something like this. The contact never changes from s@address

Is the length of the /extension too long, or the entire string too long?


I’ve had a look at the code for Asterisk 1.8, and I can’t see why this wouldn’t work. Are you sure you reloaded the configuration after changing the file?


What I found is with every change I made, submitted and applied is that it was adding the new contact and retaining the older ones. At one point I had Registrations with four different contacts. Including the s@. Once I restarted Asterisk completely, it used only the last one stored.