Topic: Getting a 500 error code on your Rails installation?
It can be REALLY frustrating to start up a new Rails app or move it from your local computer to a shared host and have it spit out 500 errors.
Don't panic - this error doesn't tell you much but you can still get past it. For starters, make sure your files have the right permissions. Run the following commands (minus the '$' sign) in your Rail's app
$ chmod 755 public
$ chmod 755 public/dispatch.fcgi (or dispatch.cgi - but don't use that!)
$ chmod -R 0666 log
$ chmod -R 0666 tmp
There's a more complete write up here if this doesn't solve the problem: