WIX0001 - Illegal character in path

[MyKeySoftMK]

I have a Include-File with some paramters. One is then name of the App that should be installed. I have add a project dependency to this project in my WiX5 project

Here the ProductVariables.wxi

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

    <?define ProductProjectName = "FxCoreMYKEYPartner" ?>
 
</Include>

Then I want to Harvest all the files of my App (FxCoreMYKEYPartner). Here the Components.wxs

<?xml version="1.0" encoding="UTF-8"?>

<!-- Import global variables -->
<?include ..\ProductVariables.wxi ?>

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

    <Property Id="InitializeComponents" Value="1" />
    
    <?define MainOutputDir = $(var.SolutionDir)\$(var.ProductProjectName)\bin\$(var.Configuration)\net8.0-windows ?>
    
    <ComponentGroup Id="ProductComponents" Directory="APPLICATIONFOLDER">
      
      <Files Include="$(var.MainOutputDir)**">
        <Exclude Files="$(var.MainOutputDir)**\*.pdb" />
        <Exclude Files="$(var.MainOutputDir)**\*vshost.*" />
        <Exclude Files="$(var.MainOutputDir)**\orders.xml" />
      </Files>
      
    </ComponentGroup>
  </Fragment>
</Wix>

I hope someone can give me a hint

I have try to put in the ProjectFoldername hardcoded - but the same error

<?define MainOutputDir = $(var.SolutionDir)\FxCoreMYKEYPartner\bin\$(var.Configuration)\net8.0-windows ?>

Then I test following: I remove the last charater of my ProjectFoldername.

<?define MainOutputDir = $(var.SolutionDir)\FxCoreMYKEYPartne\bin\$(var.Configuration)\net8.0-windows ?>

Then a build was running. But with no files. And in the Output of VS2022 i see following hint:

1>D:\_AppDev\VS2022\MYKEYCore\MYKEYPartner_Setup\Files\Components.wxs(15): warning WIX8601: Missing directory for harvesting files: Ein Teil des Pfades "D:\_AppDev\VS2022\MYKEYCore\FxCoreMYKEYPartne\bin\Debug" konnte nicht gefunden werden.

What I found out:

1. When the Path is valid, then the "Illegal charactor"-Error is comming.
2. In the path i missing the "\net8.0-windows" - can it be, that the path is ending by "\Debug"?

[MyKeySoftMK]

I use follwing definition in my ProductVariables.wxi (!) and remove the line in Components.wxs

<?define MainOutputDir = $(var.FxCoreMYKEYPartner.TargetDir) ?>