Standalone WIX uninstaller

Question

I'd like to create a standalone silent uninstaller using WIX that I can send to specific people for support purposes that can be double-clicked to execute the uninstall of our product when the uninstaller did not work properly on their machine and no longer exists (some users remove things manually using other tools). I have a .wxs file that uses the same product id and package id of the previously installed program, and if I run from msiexec /x it uninstalls the previously installed product perfectly. Double-clicking on it (which is all these users can be expected to do) however runs installation, not the uninstall. I tried adding

<Property Id="REMOVE" Value="ALL"/>
<Property Id="ACTION" Value="UNINSTALL"/>

and making sure all InstallExecuteSequence actions are not using an "Installed" check but the product is still installed after running successfully, the log file shows it is still executing ACTION INSTALL:

MSI (c) (A8:F8) [15:42:08:324]: PROPERTY CHANGE: Adding ACTION property. Its value is 'INSTALL'. MSI (c) (A8:F8) [15:42:08:324]: Doing action: INSTALL MSI (c) (A8:F8) [15:42:08:324]: Note: 1: 2205 2: 3: ActionText Action 15:42:08: INSTALL. Action start 15:42:08: INSTALL.

Is there a way to force an .msi file to perform an uninstall without using the command line or add/remove programs entries? I've seen entries about using ARPSYSTEMCOMPONENT but not enough information to do it.

Answer 1

I don't think so. You could, of course, use an exe to do it. I would also strongly suggest that you use the original msi file instead of creating a different msi with the same product code.

For the exe, you could use any number of chainer/bundler/downloaders. There is NSIS and also WiX's own Bootstrapper, ... even WinZip.

You should also note that many package management systems that run uninstall commands will run the install command first if anything is amiss. The theory is that an uninstaller can't properly run unless the critical data placed by installation exists. (E.G., WPKG). For Windows Installer, this usually doesn't apply since it's data is hidden from the user. But if they found it and corrupted it, reinstalling and/or repairing using a fresh copy of the original msi might do the job.