Not reinstall last version WiX

Question

I need that when my installer find something previously installer, it remove all before reinstall. So far I have this code:

<Product Id="GUID1" Name="MyName" Language="1033"
    Version="1.0.0.0" Manufacturer="MyManufacturer" UpgradeCode="GUID2">
  <Package InstallerVersion="200" Compressed="yes" InstallScope="perMachine" />

  <InstallExecuteSequence>
    <RemoveExistingProducts Before="InstallInitialize" />
  </InstallExecuteSequence>

  <Feature Id="ProductFeature" Title="MyTitle" Level="1">
    <ComponentGroupRef Id="MyFeatures" />
  </Feature>
</Product>

But when I running the installer I get this message: There is another versino of this product installed. This instalation cannot continue. (or something like this, my windows isn't in english).

How fix that?

Answer 1

If you want, you could use an upgrade code and versioning system to do this:

    <Product Id="*"
         Name="MyApp"
         Language="1033"
         Version="1.0.0"
         Manufacturer="Me"
         UpgradeCode="bf35a656-3e28-4f40-9ebd-566174c9c948">

         <MajorUpgrade Schedule="afterInstallInitialize" DowngradeErrorMessage="A later version of MyApp is already installed. Setup will now exit."/>

         <!-- other stuff -->
    </Product>

Key is you always keep the product code to "*" and the "UpgradeCode" constant. This will make is so that when you change the version to 1.0.1 it will remove all previous versions. However, if a user tries to install an older version when he already has the newer version it won't let him/her (unless they manually uninstall first).

Disclaimer: The same version will not trigger the update. Also changing the 4th number (1.0.0.*) will not trigger an update either. It works just fine with a 3 number versioning scheme. In order to have a four number versioning, I would look into designing a bootstrapper (setup.exe) for the software.