If you are running 32-bit Windows on a 64-bit server then that's good. But here is what the install guide says:
Prerequisites for FastBack Server (Windows only)
__ 1. Use one of the following operating systems for FastBack Server:
v Microsoft Windows 2003 Standard, Enterprise, Storage, and Storage R2 Server, Service Pack 1 or later
v Microsoft Windows 2008 Standard, Enterprise, Datacenter, Web, Storage, Small Business, and Essential Business Server
v Microsoft Windows XP Professional Edition, Service Pack 2 or later
The operating systems are only supported on the Windows x86 (32 bit) architectures and 32-bitprocessors. In addition, the boot and Windows operating system partitions must be formatted in NTFS.
This is why I am concerned.