VB.NET install to same path when upgrading application
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I have an application where I'm implementing automatic updates. I have a web service that the program checks and if it needs to upgrade it downloads and runs the new installer (Visual Studio 2005 Setup Project), after which the program relaunches. All well and good.

But how do I make sure that the installation path in the installer defaults to the same path that the user originally installed the program to?

For example, if the user changed it from program files to C:\SomeFolder, how would I make the installer detect that and change it's install path to C:\SomeFolder instead of program files? Or if the user chose to install it for "Current User" instead of "All Users"?