connecting to pgsql

I have installed postgresql with postgis on a server at my home and I
have loaded some data into it but I can not access this data from
another computer. I have downloaded the ODBC driver from the postgresql
web site and have installed it on another computer but when I try to
establish a connection to postgres through microsoft access or
arccatalogue I can not connect.

The error I am receiving says that the connection was refused. I am
positive I have the password right and the firewall is disabled but I
still cannot connect. Has anyone experienced this problem before? Is
there some default setting I have to change in postgres to allow other
computers to access the db?

Any help would be greatly appreiciated.