I've been learning how to develop on a Mac for about a year and have always been able to run a local server, for example, when developing in Ruby on Rails or Sinatra.
A few days ago I updated to Mountain Lion and I just tried to run a local server to start a Sinatra application. However, it fails with the below message:
== Sinatra/1.3.3 has taken the stage on 4567 for development with backup from Thin >> Thin web server (v1.5.0 codename Knife) >> Maximum connections set to 1024 >> Listening on 0.0.0.0:4567, CTRL+C to stop /Users/me/.rvm/gems/ruby-1.9.2-p290@global/gems/eventmachine-1.0.0/lib/eventmachine.rb:526:in `start_tcp_server': no acceptor (port is in use or requires root privileges) (RuntimeError)
I've already checked that no other ports are in use.
What can I do to be able to run the server again?