Unable to get console access over Serial

I’m trying to connect to the console on my BBB. Windows doesn’t show the board is connected in Device Manager even though I’m powering it over USB (by the way, I had it working before). I can connect to cloud9 since the BBB is connected via Ethernet and I set up a static IP address earlier. When I try to SSH using PuTTY, it fails and says “Server unexpectedly closed network connection.”

Last night, I ran “opkg upgrade” and tried to install ntp. I don’t know if doing these would have done anything serious. I’m really stumped.