I have two separate computers, each of which are running ArcGIS Desktop 10.3.1 and PostgreSQL and PostGIS 2.1.7. The only difference is one is running PostgreSQL 9.3.4, the other is running 9.3.5.
I am trying to make a simple (or what should be simple) connection to DBMS. I have properly copied all of the PostgreSQL client files ( libeay32.dll, libiconv-2.dll, libintl-8.dll, libpq.dll, and ssleay32.dll) to the ArcGIS bin directory. The pg_hba.conf for each is set to accept client connections. And, of course (of course!!!), I have no problem whatsoever connecting to either using other clients, such as QGIS. However, when I try to add a database connection using ArcGIS Desktop, it works splendidly on one machine (the one running 9.3.4), but not on the other. The error I receive is “Unable to connect to database server to retrieve database list; please verify your server name, user name and password info and try again. Cannot connect to database because the database client software failed to load. Be sure the database client software is installed and correctly configured.”
I have searched high and low to solve this issue and, as a result, have wasted more time than I would like to admit. I am debating if it is more maddening than frustrating or vice versa. If the option was to use another client, such as QGIS, I would. Obviously, it is not. Since I can connect just fine on one machine, I know it actually should work (and the version difference of PostgreSQL really shouldn’t matter).