Postgres.app Could not start on port 5432

Question

I\'m using http://postgresapp.com. In the menubar it gives the error \" Could not start on port 5432.\" Similarly if I try to start the server from the terminal, I get:

Answer 1

A file named "postmaster.pid" (in my $PGDATA directory) were preventing postgresql to start. It was a zombie file, placed there 10 days ago and when I brutally shut down the computer (pulling the plug, literally), no clean up process had the opportunity to remove that file.