Personal Firewalls: Recent releases of anti-virus come with built-in firewall features that you may not even be aware of.

Many broadband internet users now have a firewall on their home connection.

Many home routers have firewall's built-in, but most user's have a software firewall.

The most common is Zone Alarm.
Zone Alarm causes problems with WebCT because it blocks the network ports that WebCT uses. It can also cause a problem because it doubles as a content filter. Zone Alarm can prevent javascript or java applets on websites from working on your browser. WebCT uses both javascript and java for a number of its tools.

Note: Even if you enable access to the WebCT site, you may STILL have to disable the "anti-popup feature" AND disable the "anti-javascipt feature."