Placing a free call via internet, be it WiFi or 3G, involves quite a bit of routing, and system updates, especially with international calls, and is also dependent on the quality of both user's devices.

Also please bear in mind that other applications may be running in the background of your device, or your friend's device, which may compete with bandwidth.  And, be aware that all users do not have similar devices, and Viber may run better on some devices than others (please visit http://support.viber.com for a list of tested devices).

If the connection is weak, or not active, this may cause errors such as setup not being able to process and proceed, contact list not visible or not properly updated immediately, no clear audio reception, no internet error message (when in fact you do have internet running).

Connection issues may be caused by different reasons such as:

* System upgrades on our end or no internet on your end - you will receive a "not connected to internet" error, or you may have trouble receiving a registration code,
or Viber may ask for you to re-register.

* Viber friend is not connected to the internet

* Viber friend’s number not listed correctly in address book

* WiFi Firewall settings

* Service provider issues

We recommend that you try to connect at a later time. If this still does not solve the issue, try to reinstall the Viber app.

If you are using WiFi, and you have never been able to connect through it, it may be that your firewall ports are closed.

 * WiFi Firewall settings:

Please have the systems administrator go to the WiFi firewall settings to make sure that the below ports are open for both sides:

1) TCP 5242

2) TCP 4244

3) UDP 5243

4) UDP 7985



Viber friend is not connected to the internet: If the person you are trying to call is not connected to the internet, they will not receive any Viber calls. You will still hear a ringing when calling a disconnected user.However, they’ll get a missed call notification when they turn their internet back on.  On your end, during the placing of the call, you will hear a ringing until it times out.

If you look at your screen during the call, it will say 'connecting' rather than 'ringing'. This is because the call was not able to connect due to the receiver of the call not being logged onto internet via their WiFi or 3G.

 

Here's a short list of other things that may help you work through this if the above did not work:

 

* Please turn your phone off, and then reinitiate it.

* Please check the system requirements for Viber:

     Please click HERE for further information.

* Uninstall/Reinstall:

     Please click HERE for further information.

* Contact phone number listed properly for Viber calling?

In order for your contacts to see you as a Viber user, and connect with you, the telephone number which they have listed for you in their contact list must be the exact same number as you have registered with in Viber. And visa- versa.

For example:  Some people use different long distance dialing codes as prefixes, therefore, if you registered your Viber with your country code as 1 and your cell provider code 234 and your telephone number 5555555, and your contact has you listed as he would usually call you via a regular GSM call, i.e., with their long distance access code first; [XXX] 1 234 5555555, your friend will not see you as a viber user.  This works both ways.  Your friend will need to add another entry to his contact list for your number as +1 234 5555555

* Service provider issues:

Please check with your carrier if they have blocked certain applications from connecting through their 3G network. It is a known issue that some Viber users cannot connect through 3G network and in some cases have verified that this is due to network blockage on their carrier’s side. If this is the case, then unfortunately, Viber will not be able to bypass your carrier's network blockage.  It is in your carrier’s decision which applications they wish to provide or block network availability. This also goes for other blocked applications, such as Viber that cannot connect through 3G.  No worries though – simply use your Wifi as an alternative connection :)

Stay tuned!
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