Windows Installer Updates

Windows Installer update files allow the binary content of a Windows Installer installation to be changed without having to distribute an entirely new Windows Installer file. Office XP hotfixes and service packs use Windows Installer update files.

Windows Installer uses an update package to modify local or administrative installations. An update package is a file with an .msp extension that can contain a modified version of any component in the original .msi file. An update might contain a portion of the binary information for a particular component. Therefore, in most cases, the update relies on the original installation .msi file to be available when the update is applied.

There are two types of Windows Installer updates that Office XP can use:

  • Administrative updates

  • Client updates (also called standard updates)

Any particular fix encapsulated into a Windows Installer update file has two different versions of the update specific to each of these types. An administrative update cannot be applied to a client installation, and vice versa. The following sections describe these updates in more detail.

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Administrative Updates
Client Updates

Administrative Updates

Administrative updates apply the Windows Installer update to the original Windows Installer source (the source on the SMS distribution points or, for most deployments, Windows Installer source servers). An advantage of this method is that it permits new client installations of Office to install the latest update components without needing separate distributions of updates. A disadvantage of this method is that clients that have not been instructed to install the new update cannot use this source for maintenance operations such as adding, removing, or repairing an installation until they have synchronized with the latest source. This is because the original Windows Installer source is changed (the package code of Windows Installer is changed). As a result, there is a risk that clients with Office installations can become orphaned, unable to run repair operations from the source, until they are instructed to apply the update. However, correct deployment of updates using SMS can mitigate this risk considerably.

Client Updates

A client update, also called a standard update, is a distribution of the actual .msp file to individual client computers without changing the original source on the server. One advantage of this is that the server Windows Installer source remains valid for both updated and non-updated clients for maintenance operations. As a result, users do not experience problems using Office XP. One disadvantage of this method is that new client installations receive only the original Office version. They still need to receive the specific update distributions to update to the required Office component level. However, if the updates are being targeted using SMS software inventory information, then the update occurs with no administrator intervention. However, additional client programs must run and a delay occurs in updating the client Office installation to its required state. As a result, client updating requires more SMS administrator overhead than administrative updating.

In most situations, the original Windows Installer source is required when you are applying an update. For reliable updating, the original source should always be available when applying a client update.

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