Bear in mind that Squawkbox 4 is in public beta - there are bugs in the software - beta tests are about reporting those bugs so that they can be fixed.
There are known issues related to using Squawkbox with Antivirus and Firewall software packages.
I suggest you post on the
VATNZ Forum, look at the
official Squawkbox forum, or take a look at the
Squawkbox sub-forum on VATSIM Forums.
Specifically,
this thread on VATSIM Forums looks like it may have the answer;
If that doesn't work, or you would rather find a permanent solution, try allowing the TCP and UDP ports that Squawkbox uses - these should be listed in the Squawkbox manual.
EDIT: I just did a search of the manual.
Set up Norton to unblock the ports mentioned in the following quote;Squawkbox Manual wrote:For connecting outside your local network, SquawkBox uses TCP port 6809 and UDP port 3290 for outgoing connections only. SquawkBox does not accept any incoming connections. The DirectPlay system used by Microsoft Flight Simulator for multiplayer functionality uses a number of network ports, but those are only used internally for communication between Flight Simulator and SquawkBox.
While we're on this topic, if anyone else has any issues with VATSIM software that they would like other members to offer advice on, please feel free to ask

We're here to help

Hope that helps,
Matthew