For the last 10 days, Multiplicity has not been working correctly on my 2ndary computer. I upgraded to Multiplicity Pro yesterday after uninstalling Multiplicity. After installing on both machines without problem and rebooting, the primary doesn't see the 2ndary machine (gives the message about the firewall, and port). The way around it has been to use the troubleshooter in the 2ndary machine and then the primary is able to see it and works correctly. Any idea why this is happening?