Windows 7 - PgAdmin II no longer connects to databases

I upgraded my PC to Windows 7 from XP SP2

 

PgAdmin III latest release works fine on Postgres 9

 

BUT I use PgAdmin II 1.6.0 on an old AIX server that has Postgres 7.1.2  (updating is NOT possible)

Worked fine in XP, now it refuses to connect to the databases.

It shows correctly the list of databases but when clicking on one, it shows a red cross on top of the DB icon and on the right panel the Connection Status says : Inaccesible

 

It is odd since it sees correctly all the properties of Postgres and the databases, but will not show the tables, etc.

 

i tried to run PgAdmin II in compatibility mode with no success. Any ideas?

 

Thank you