I am new to the elementary OS Freya. Have been using Ubuntu for good time now. I upgraded the system in the morning and after upgrading, the file manager "Files" wouldn't open up. There were a few problems in the Mozilla Firefox after the upgrade though couldn't really get the reason for that.
I tried installing "Files" again and also installed "Pantheon" but to no avail.
I had to run nautilus from the terminal to access the files but that gave plenty of errors in the terminal window.