|Windows Installer Basics: Source Availability|
The msi is obviously available for the original install, however for any installation activity that occurs after this (a repair) it may or may not be (the user may have deleted or moved the msi are removed the DVD media from the drive).
If the msi is required and unavailable then Windows Installer will look for it in the original location where it was installed from and if this is removable storage will prompt for it (whether you can browse for it etc will be controller via Windows Installer policies). Otherwise it will search other locations it has been told about, its "source list" (see below for more on this).
If it can't find a suitable msi source it will prompt with something like:
To reduce the need to "annoy" users for cd-roms or dvds Windows Installer caches a modified copy of the msi on your local drive.
There are things you can do which will force the requirement of the original msi (not ideal, avoid where possible), a partial list:
|Source List - Windows Installer Searching for msi|
As mentioned above, Windows Installer has a list of locations it will search for the MSI source if it needs to install files, this is called the "source list".
There is no user interface for changing the source list, however there are some tools available and you can use the Windows Installer API or the Installer object's methods (such as "AddSource()"). Windows Installer versions prior to 3.0 only had very basic support.
|Make Your Own Permanently Available Copy!|
By default Windows Installer will look in the location the msi was originally installed from, making it a good idea to install from a location which is always available (fixed network location or from a local drive). Bootstrap installers will almost always extract the files to your hard disk before invoking the installation so that it is permanently available.
One way to install the file from a variable location using a fixed name (no need to manage the "source list") is via a DFS (Distributed File System - similar concept to a drive "letter"), that way the same location can be used for all installs and the DFS can be mapped to appropriate (and replicated) locations.
To create a network image from multiple media an administrative install is the best way. For a simple standalone MSI or single media it is probably easier to simply copy the required files.
|Some Related External Links|