Components are the basic unit of installation in a Windows Installer product. They are installed by one or more features, and can contain any number of resources including files, assemblies, registry values, and are recommended for custom resources as well.
When installing a patch package, Windows Installer first determines if the patch is applicable. Depending on how the patch is installed, this happens a little differently. Windows Installer can determine the list of applicable products, or it can be told to which products the patch should be applied.
Language support in Windows Installer can be confusing until you understand how Windows Installer queries for and uses languages. Some wonder why Windows Installer packages have two different places to set the language. Some wonder why, for example, localized packages install using a different language than the user’s default UI language.
table in a Windows Installer package has a Sequence column that begins with
1. Besides determining in what order files are to be installed, this column
serves another, relatively more important function: determining where the source
files are located.
When problems occur when installing, repairing or patching, or uninstalling a product using Windows Installer technology, you need to be able to figure out what happened and why it happened. Dialogs that occur when the user interface is displayed can be helpful sometimes,
A Windows Installer database is full of strings. Most times those strings don’t cause a problem when using the standard, printable characters found in all code pages. These are called ASCII characters and are the same for the first 7 bits (0x00 through 0x7F) for all code pages except for a few rare code pages in existence for legacy support.
Previously I blogged about what is in a patch, but how do patches work? To put it imply, patches transform a view of the product or products that the patch targets.
Patches (.msp files) contain a set of transforms: one transform changes the target product into the upgraded product,