Upgrade Merge Module distribution with MSI package
Hi, I haven't been here for a while, but as I'm helping out on some installation issues I need some help.
We had a merge module created with IS2008 distributing App version 1 (MMAppV1) in various MSI installation packages.
Now we are reworking the App v1 of this merge module to App version 2 and need to change how we distribute the content. We like to use a new msi installer (MSIAppV2) to make sure that we can easily patch the App v2 with additional language files and patches.
When we now run the newly created MSI installation package for MSIAppV2 we need to ensure that App V1 is uninstalled, which was distributed in (MMAppV1) as part of various MSI packages
Currently we are stuck how to trigger the upgrade of App V1 within the MSI package for App V2.
As there is no upgrade code for merge module (MMApp1) we can't use the path of unrelated product upgrades.
Is there a recommended way of achieving this or are we stuck?
The key to this is that a merge module is just a collection of components that become part of the .msi you create. If you want to run a minor or major upgrade of those components, you have to do it at the .msi level.
Now if you just want to upgrade the files that were installed by those components, and if they are installed to a shared location, you can create another .msi that doesn't have to be related to the one that installed the files originally. Follow all the rules for shared components (use the same GUIDs, same locations, same filesets but with increased version blocks, and so forth), and this other .msi can upgrade the files.
However if the files don't go into a shared location, then each .msi that consumed the merge module will have to upgrade its local copy of the files with its own upgrade. This is the rub of merge modules, and why Microsoft has largely stopped shipping them.
