Create or update MSI (Windows Installer) based installers for files, registry etc using an XML like script.

Can use in unattended builds (NMAKE, ANT, NANT builds etc).

It builds a HTML report by default (with a "file verify" button).

For both beginners and advanced users.

Common processes can be defined once and reused in multiple projects (templates).

Has extensive documentation and a large user group (480+ members).

A MSI compare or disassemble tool is available which generates MAKEMSI output, this is commonly used by people wishing to automate tasks they currently use ORCA for. Also has a framework for easy MSM (merge module) and CUB (MSI validation suite) building.