>At a client site I have had an application accessing a firebird database on their server (both workstation and server are 32bit) without any problems.
>They have now added a workstation with a 64bit operating system and can't seem to be able to access the database from it.
>Have installed 64bit Firebird (Ver 2.1) on that workstation.
>The more I Google information about this situation the more I get confused because of contradicting advice and incomplete answers.
>Can someone please explain (in simple steps) what needs to be installed and/or configured to make a 32 bit application on a 64bit machine
>access a firebird database on a 32bit machine.

A 32 bit app will work perfectly happily on a 64 bit machine, so don't think you *have* to put the 64 bit version on, just because you have a 64 bit machine.

Generally, 32 bit EXE and DLL's, aren't going to be able to communicate with 64 bit DLL's, so you need to keep them all the same.

Since your application is 32 bit, I would therefore choose the 32 bit version of the Firebird client for your 64 bit client PC.

Since your server is also still 32 bit, you are not going to missing out on any new features either, I don't think. (new features just being the ability to access more ram AFAIK)