Platform identification in WiX 3.0

Question

I am facing issues when migrating the managed code from x86 to x64 platform. I have a WiX project to create an MSI which will be executed through Bootstrapper.

On an x86 platform, files get copied in “Program Files” as per the Project.wxs file. But if the same MSI is installed on an x64 platform through Bootstrapper, all the installation files get copied by default in “Program Files (x86)” and the application’s functionality failed as it could not find the necessary files in the 12-hive hierarchy of Program Files (for 64-bit it is “C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\CONFIG”).

I have tried using preprocessor variables like <?if $(var.ProcessorArchitecture)=x64 ?>, but I need to hardcode this variable in the project property to either x86 or x64. Finally I end up with two different MSIs for two different platforms which is not a desirable solution for me.

So, through WiX, is it possible to identify the platform to ensure installation at the desired location?

Answer 1

I don't believe you will be able to have a single MSI that will support both platforms. You will need to create one for x86 and another x64 - the good news is that you don't need to maintain another WiX project to achieve this.

The way I've done this in the past is to have the following at the beginning of your product definition.

<?xml version="1.0" encoding="UTF-8"?>
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">

    <?if $(var.Platform)=x64 ?>
      <?define msiProductId = "102F7DF4-19A6-4d3d-987F-FF57A2031593" ?>
      <?define win64Flag = "yes" ?>
    <?else ?>
      <?define msiProductId = "8AE46CAF-220F-4B9F-9527-D4A19A27C45B" ?>
      <?define win64Flag = "no" ?>
    <?endif ?>

    <Product Id="$(var.msiProductId)"
             Name="My Product"
             Language="1033"
             Version="1.0.0"
             Manufacturer="Acme"
             UpgradeCode="E2575E4A-A62E-4460-B96D-B722C79C8EAA">

        <Package InstallerVersion="400"
                 Compressed="yes"
                 InstallPrivileges="elevated"
                 Platform="$(var.Platform)"
        />

        <!-- Rest of product definition goes here -->

    </Product>
</Wix>

I forget where I got the advice to use a different ProductID for each platform.

I created the 'win64Flag' variable to get other WiX elements to work nicely in the cross-platform scenarios. As an example, here's how you use it to make a single RegistrySearch definition work for both platforms and should resolve the issue you are having with locating the 12-hive hierarchy.

<Property Id="WSE12DIRECTORY">
    <RegistrySearch Id="Reg_WSE12DIRECTORY"
                    Type="raw"
                    Root="HKLM"
                    Key="SOFTWARE\Microsoft\Shared Tools\Web Server Extensions\12.0"
                    Name="Location"
                    Win64="$(var.win64Flag)"
    />
</Property>

With all this in place, then it is just a case of passing the relevant value for the 'Platform' pre-processor variable on the Candle command-line, or selecting the target platform in Visual Studio.