Ok. I think I figured out my problem. I used SSH to connect to my RPi, but accidently connected to the wifi IP and therefore my RPi couldn't connect to the internet (via wifi). However, when I use the eth0 IP ,my connection is dropped or refused. It won't connect.

I was having the same problem as the original post. I ran the command to remove ifplugd, however it replied that it wasn't installed, so it wasn't removed. What else could be the issue?