I think pgAdmin v1.20.0 was compiled with the same VS chain (2013 as I recall) as the PostgreSQL 9.4 binaries. These don't work on Windows XP. Probably should be noted somewhere on the site that Windows XP is not supported. So you have to use a lower version of pgAdmin III . Also you can't use PostgreSQL 9.4 on windows xp either. I ran into the same issue when a PostGIS user complained about the issue (wanting to run PostgreSQL 9.4 and PostGIS on windows xp ) and had to put a notice on the PostGIS windows page to that effect. Hope that helps, Regina
_____ From: pgadmin-support-ow...@postgresql.org [mailto:pgadmin-support-ow...@postgresql.org] On Behalf Of Melvin Davidson Sent: Saturday, December 20, 2014 12:51 PM To: pgadmin-support@postgresql.org Subject: [pgadmin-support] PgAdmin III 1.20 windows - not valid My O/S is Windows XP Pro SP3 I just downloaded PgAdmin III v1.20.0 from http://www.postgresql.org/ftp/pgadmin3/release/v1.20.0/win32/ After installing, I get the following error when trying to run it: " (null) is not a valid Win32 application. " To reproduce: 1. download .zip 2. Open .zip and click on pgadmin3msi 3. Follow prompts to install 4. Click on link to PgAdmin III 1.20 Melvin Davidson I reserve the right to fantasize. Whether or not you wish to share my fantasy is entirely up to you. <http://us.i1.yimg.com/us.yimg.com/i/mesg/tsmileys2/01.gif> Folk Alley - All Folk - 24 Hours a day www.folkalley.com