I am unable to use the PC-to-PC voice feature due to a connection problem. What might be causing this?
You might have a firewall blocking Yahoo! Messenger's PC-to-PC voice feature. If so, you need to open up some outgoing TCP connections. Note that it is the outgoing connections that matter, not incoming connections. In most firewalls, you have to specify a destination port or port range to open. Learn more about which ports Yahoo! Messenger uses.
Even if you don't use a firewall, your Internet service provider (ISP) may use a firewall, a network address translator (NAT), or a proxy server that blocks voice traffic. Any of these could prevent you from using the PC-to-PC voice feature in Yahoo! Messenger. Please contact your ISP's network administrator for assistance getting around these issues.
Where's the Contact Customer Care button? With so many improvements to Messenger since the version you're using (lots more features and reliability), we figured you're ready to move up. So get your upgrade and with the new version, rest assured if you have questions, you’ll find that friendly button on its help pages.
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