I have an iPhone 5 (iOS 6.1.1) and I installed Viber messenger (version which enables you to make phone calls over the internet. The messenger works perfectly when I use a wireless router to connect to the internet (which I don't have at home) but when I connect to my Windows XP ad-hoc network, I can't make phone calls. the call is dropped after 3 to 4 seconds and I can't receive calls either. This only happens on my ad-hoc network.

  • The computer connects to the internet through 3G modem
  • I tried updating to the latest version of Viber (2.3.1) from apple but no good
  • My friend has an older iPhone (probably 3G or 4) and he has the same exact version of Viber. When he tries to use my ad-hoc network, it works and he can call and receive calls.
  • I can't use my 3G sim card directly on my iPhone, I have to go through the ad-hoc network.

What could be the problem and solution to this dilemma?

  • When you look at the iPhone's IP settings, what do you see? (click the arrow next to the network name in Settings..Wi-Fi) A screen shot would be ideal. Commented Apr 3, 2013 at 20:12
  • @MatthewElvey, the IP is assigned from the DHCP server on my laptop, the subnet mask is as usual and the router and DNS are which are the addresses of the laptop. i tried using a proxy server but no good too. Commented Apr 3, 2013 at 23:05
  • did you try to remove Viber and download again from app store? Commented Apr 9, 2013 at 9:55
  • @GuidoPreite, yes with no avail. Commented Apr 9, 2013 at 12:26
  • same here. i think it may have to do with a port on the laptop which viber requires to pass thru to connect. anybody can help? tango and facetime have no problems. only viber.
    – user50831
    Commented Jun 7, 2013 at 20:45

1 Answer 1


Because your friends iDevice works, it may make this consideration useless. http://www.viberfaq.com/why-cant-i-use-viber-on-some-wi-fi-networks/ suggests that these ports are required for Viber to work.

  • TCP: 5242 and 4244
  • UDP: 5243 and 7985 (9785) (7985 is the port specified on the Viber) troubleshooter

However, the symptoms of having closed ports would be no connection to Viber. Maybe there is an application taking these ports on your Windows Machine intermittently.

  • I am sure those ports aren't taken by any software, and i have turned windows firewall completely, yet no good. Commented Jun 7, 2013 at 22:09
  • Thanks for sharing TCP n UDP port numbers and allowing them through proxifier.. Now I can go through Viber in Win7 Laptop with Domain/proxy controller.
    – user93420
    Commented Oct 3, 2014 at 16:07

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .