Patching
About MSI patching
Patches are packages that contain only the changes between two MSI packages. Therefore, they are a very compact method of distribution for small updates. MSI 2.0 provides many patching enhancements, as does MSI 3.0. These are described in more detail in the MSI documentation. Wise Installation Studio allows you to author .pcp files (which are essentially blueprints for patches, not the patches themselves). Wise Installation Studio can then build the .pcp files into .msp files (the actual patches, which consist of a set of transforms). Patches should only be used for distribution of small updates. It is often easier to distribute a completely new package if there are great differences between that package and the original package.
To learn more about patching, see the Windows Installer documentation.
Authoring patches with Wise Installation Studio
To create a new patch project with Wise Installation Studio, follow these steps:
- From the File menu, choose New.
- Select Patch as the project type.
- Enter a project name and path.
- Click OK.
- Follow the instructions provided by the Patch Wizard.
While using the patch wizard, you run into the concept of the original package and the updated packages. The original package is the installation package targeted by the patch. That is, it will be updated by the patch. The updated package is the package used to create the patch. The patch, when applied, should convert the original package to the updated package.
Building and distributing patches
To build your patch, follow these steps:
- From the Build menu, choose Build.
- Have a look at the build status in the Output Window (at the bottom of the main Wise Installation Studio window) to see if the build was successful.
To distribute your patch, open the build output folder (by going to the Tools menu and choosing Open Build Folder). The .msp file is the only file that you must distribute. If you're distributing it over the web, you may wish to package it using a compression tool.