If you have a problem making or receiving video or pc-to-pc voice calls, the reason may be due to one of the parties being behind a firewall.
Firewalls are security devices put in place to refuse certain connections from outside computers to your local network.
SightSpeed uses direct connectivity between you and the person you are calling while the call is in progress. If your firewall is activated, SightSpeed will attempt to traverse it, but sometimes this can fail. If this happens, the call may not be able to go through.
To resolve problems with firewalls, you can configure your router's firewall or configure your software firewall.
For in-depth help on firewalls see our support site.