I just installed Ruby on Rails on a server at home, but after running the WEBrick server I got the following error:
MissingSourceFile in <controller not set>#<action not set>
After looking around for a few minutes I found out that this was caused by how I was running WEBrick. Basically you have to run it from the main application directory and not the script directory. So you should always run "script/server" instead of "./server" inside of the script directory.