Thank you so much! As of now, I can connect to both Ethernet and Wifi. I did remove Symantec before downloading Avast, so that couldn't have been the source of the problem. My problem with Symantec is that it wouldn't let me perform a LiveUpdate for some reason, so Clearpass had me quarantined. Right now, I'm still using Avast, and I started being able to connect to wifi after using your firewall solution.

The Ethernet issue was a lot more strange. Clearpass was showing me a green, healthy screen when connected to Ethernet. However, I would suddenly stop being able to load a webpage every minute or two. Clearpass would still be healthy, but I would have to either log out and log back in or unplug my Ethernet cable to get it to work again. Thankfully, the Ethernet started working out of nowhere yesterday, and I haven't encountered the problem since. I didn't change any setting or do anything in particular, so I'm not sure how it resolved itself. However, I have still heard from at least two of my friends that they also have the disconnecting Ethernet problem.

Again, thanks a lot for your help!