Converting Wix v3 installer project to Wix 4 (heatwave). Error related to xmlns = http://wixtoolset.org/schemas/v4/wxs

[disco-sai-gattu]

HeatWave Version

4.0

Visual Studio Version

22

Repro Steps

1. Upgrade wix v3 project using the VS project context menu.
2. Allow it to upgrade automatically
3. Build the solution
4. There is a build error :
   Severity Code Description Project File Line Suppression State
   Error WIX0199 The Wix element has an incorrect namespace of 'http://schemas.microsoft.com/wix/2006/wi'. Please make the Wix element look like the following: . ProjName C:\r\ProductNameBin.wxs
5. ProductNameBin.wxs is a file we created for Wix v3. It used to xmlns = http://schemas.microsoft.com/wix/2006/wi, but the error message suggests to change the xmlns to http://wixtoolset.org/schemas/v4/wxs.
6. Even after change the xmlns in ProductNameBin.wxs the error comes back and xmlns changes back to original xmlns which is 'http://schemas.microsoft.com/wix/2006/wi'

Actual Result

Build error stated above

Expected Result

Solution should build fine after upgrading wix v3 project to Heatwave/Wix 4

[FireGiantHelp]

Can you share the project that is causing this issue? This behavior is very strange and unexpected.

[gerrycoll-myob]

I'm getting the same issue. Using Visual Studio 2022 Professional 17.8.7, I upgrade the project and get

<?xml version="1.0" encoding="utf-8"?>
<Wix xmlns="http://wixtoolset.org/schemas/v4/wxs">
    <Fragment>
    <!-- ... -->
    </Fragment>
</Wix>

When I choose "Build" from the menu, this get changed back to

<Wix xmlns="http://wixtoolset.org/schemas/v4/wxs">
    <Fragment>
    <!-- ... -->
    </Fragment>
</Wix>

Oddly this only happens for two out of six of my wxs files.
note that the <?xml > tag is also added.

I committed the changes locally to git, and then also tried while disconnected from the Internet with the same result, so nothing is being reverted from git,