Hi Andrew,
Based on my understanding, what you want to do is to do some preprocess before installing the MSI package, right?
I am not sure which process you want to do, but Visual Studio allows you to add Launch Condition to the setup project. This means some conditions that must be met in order to successfully run an installation. For example, you might want to check for a specific version of an operating system �if a user attempts to install on a system that does not meet the condition, the installation will not occur. For more information, please check the following page:
You also can use the Orca tool to add custom action and set the custom action’s sequence to make this custom action run before the installation executes.
Another choice is that you can create your application to do the process. And start the installation after the process complete.
Let me know if this helps, if not, could you please clarify what you mean by 'extra process'?
Best regards.
Rong-Chun Zhang
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