Where is the Postgresql config file: 'postgresql.conf' on Windows?

I'm receiving this message but I can't find the postgresql.conf file:

OperationalError: could not connect to server: Connection refused (0x0000274D/10061)
    Is the server running on host "???" and accepting
    TCP/IP connections on port 5432?
could not connect to server: Connection refused (0x0000274D/10061)
    Is the server running on host "???" and accepting
    TCP/IP connections on port 5432?

Solution 1:

On my machine:

C:\Program Files\PostgreSQL\8.4\data\postgresql.conf

Solution 2:

postgresql.conf is located in PostgreSQL's data directory. The data directory is configured during the setup and the setting is saved as PGDATA entry in c:\Program Files\PostgreSQL\<version>\pg_env.bat, for example

@ECHO OFF
REM The script sets environment variables helpful for PostgreSQL

@SET PATH="C:\Program Files\PostgreSQL\<version>\bin";%PATH%
@SET PGDATA=D:\PostgreSQL\<version>\data
@SET PGDATABASE=postgres
@SET PGUSER=postgres
@SET PGPORT=5432
@SET PGLOCALEDIR=C:\Program Files\PostgreSQL\<version>\share\locale

Alternatively you can query your database with SHOW config_file; if you are a superuser.