The Windows Installer (formerly Microsoft Installer) is the management application for MSI files. It provides users with package installation and removal as well as maintenance. MSI packages represent structured storage of relational databases, thus they can also be edited as databases.

Orca may be easily considered the Microsoft Access of Windows Installer packages. It supports not only the basic databases (MSI files), but the merge modules (MSM), database patches and transforms (MSP and MST) or the validation modules (CUB) and patch creation (PCP) too.

Although it can be used as a package authoring environment, Orca is mainly recommended for its powerful editing features. It also requires database-related knowledge as it can directly modify the tables of the supported files, thus faulty operations may result in corrupt installers.

Orca will provide users with a professionally-looking environment. It presents a simple, clean and classic interface with everything you need to get the job done in the right place. Users will be able to access the tables and data streams of the loaded database and perform modifications on-site. Tables can be imported and exported while schemas can be adjusted.

The application also comes with in-depth transform management, validation tools or module merger. Orca will not hold you back from editing every aspect of your current package, whether there is a file, directory, COM component, registry key or shortcut. Everything is editable. We can easily create transforms in order to modify the data structure while keeping an eye on the integrity of the database.

One thing we have to keep in mind here is that these packages are extremely fragile and that no matter the customization level, we are able to alter the contents of the database to the point of no return. This is the only thing to watch out for in the process as the most probable outcome will ruin your hard work.

These features pack a very sturdy backbone for MSI editing as editors will relish the prospect of streamline Windows Installer package authoring. If you're an enthusiast in this field of data manipulation, then Orca is the proper toolbox you need to take MSI authoring to the next level.