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SIP-T20P: Register Failedand and no Call - Printable Version

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+--- Thread: SIP-T20P: Register Failedand and no Call (/showthread.php?tid=3115)

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RE: SIP-T20P: Register Failedand and no Call - sylviog.jr - 01-19-2015 09:12 PM

Dear Daniel , I have already connected 12 phones here. Thanks again. The information I have written are wrong. We have 3 branchs in another cities and need to connect many phones there accessing this network here. My only option is the Internet.
But I am confused on how to use STUN server and client. (
If you can point me to any tutorial to do this. Need a program? Where can I download? 3CX have?

Thank you for your attention.


RE: SIP-T20P: Register Failedand and no Call - Yealink_Daniel - 01-21-2015 10:16 AM

Dear Sylvio,

About your scene, if you want the other phones which in other cities of your company register in your PBX and be able to communicate each other, I suggest you use our OpenVPN function.

About how to install the OpenVPN Server and how to configure this feature on IP phone, please refer the guide below.

About STUN, please refer these steps to configure the parameters in your phones:
To configure NAT traversal and STUN server via web user interface:
1. Click on Account->Register.
2. Select the desired account from the pull-down list of Account.
3. Select STUN from the pull-down list of NAT.
4. Enter the IP address or the domain name of the STUN server in the STUN Server
5. Click Confirm to accept the change.

For more information, please refer page 418 of the Administrator Guide.
Link: Yealink_SIP-T2xP_IP_Phones_Administrator_Guide_V73_40

About how to build a STUN server, could you please contact your server provider or administrator for help ?
Because it’s build in your local and provide by your server provider or administrator.

Thank you.

Best Regards

RE: SIP-T20P: Register Failedand and no Call - sylviog.jr - 02-04-2015 11:36 PM

Dear Daniel,

I have progress on VPN but believed that setting up the modem or access router , opening port 1723 for VPN connection, could connect at least one phone in each branch .
I have to test :

1 computer on my local network that would be the client.
I set up a VPN connection with public IP. Setup:
Login : sylvio
Password: xxx
I visit the " yougetsignal " and tested the port 1723 (server). It´s open . I got the server remote address "".

1 computer ( server ) connected to ADSL ( GVT in Brazil , only for testing ) ,
DHCP: to
Modem opening port 1723
Port forwarding port 1723 to ip PC (router)
DMZ off
DDNS off

Router simulating a server:
Router IP :
DHCP: range to 199
Virtual Server List :
Name: VPN
Application: PPTP
Port : 1723
Protocol: TCP
IP :

Config the input connection to VPN (server)
Login : sylvio (administrator)
Password: xxx
IP range to 199 .

error 800 the remote connection was not made ​​because the attempted vpn tunnels failed

If I can not solve this not be able to install the phones.

Please help me ,


RE: SIP-T20P: Register Failedand and no Call - Yealink_Daniel - 02-07-2015 01:04 PM


Thank you for your feedback.
I will investigate about this and will let you know the result as soon as possible.

Best regards

RE: SIP-T20P: Register Failedand and no Call - Yealink_Daniel - 03-03-2015 04:45 PM

Dear Sylviog,

Sorry for reply you late.
About your issue, could you please help to get a Level 6 system log, PCAP trance and a config.bin for our investigate.
Please refer the FAQ:

Thank you for your cooperation.

Best regards