Regarding Google Translator sucks, I'll try to do my best to translate my latin colleague:
"Since I installed Mcafee Enterprise Firewall I cannot connect to Skype. I've already opened 80 and 443 TCP Ports. Please help"
Ah yes ok, 'Since I installed the firewall...' makes more sense.
I thought "I could not connect to Skype to install the firewall" was a bit off. I had GTranslated his question but it did not make sense to me.
If you make a new application on TCP ports 80 and 443 Skype will work. It will not work through the HTTP application, as it does not pass port 443 traffic (the SSL/TLS application passes port 443, but that will not pass Skype either I don't believe, since it's not true HTTPS).