Wi-Fi OK, Network has IP address but apps can't access internet

I have recently moved from Europe to Canada. My MacPro came out of the removal-container physically unharmed, started up nicely, found the new wireless network, was connected to the internet, got an IP address (all according to the Network System Prefs Pane) but unfortunately and unexplicably, NO apps can access the internet. Safari can't, Mail can't, etc. What could possibly be the problem? Again, it's not the Wi-Fi. I am using it for my MacBook, iPhone, iPad, works fine. Wi-Fi indicator in the OSX menubar also shows the network, full strenght, again no obvious problem here but no link so to say with any of the apps. Anyone any ideas why and how to solve the issue?