Originally Posted by Arbab Ali Shah
Im in Pakistan.. Ufone is the cellular network
the problem occurs on wifi network as well as my cellular company's internet facility
It could be that the network you are connected to is blocking Viber's traffic.
1. First, please try uninstalling and reinstalling Viber when connecting to a few different WiFi networks (in order to pinpoint the source of the problem). What are the results?
2. Also, please make sure the following ports are enabled ("forwarded") on your routers or firewalls:
TCP: 5242 + 4244
UDP: 5243 + 9785
(if you are not sure how to enable ports, you may contact your router manufacturer)
* Note that some mobile operators across the world block Viber on their 3G network. Usually this happens when users have a "simple" data plan (or a prepaid contract), meaning they didn't pay extra for using VoIP on their 3G network.
In order to verify this, we recommend that you contact your cell company and confirm this with them.