Dear all
really , I am tried many times to connect the PostgreSQL via pg-admin on evry time the reslut is failure, please help me

Note postgres was install under the Ubuntu Linux



@stephocay please assist our friend @Mosab with this, thank you.

Mosab the default installation of postgres on ubuntu is fairly secure out of the box. It will refuse to accept connections from outside. Rather than explaining how to open your postgresql up to world I would suggest that you keep it with its default good settings.

If you must connect to postgres with pgadmin, the safest way to do it is by setting up an ssh tunnel for this. If you google you will find many howtos.