Print Support Application - Invalid Appx Manifest

i want to create a PSA (Print Support Application) using dotnet 9.0.300 and Windows 11 SDK. I'm using VS Professional 17.14.2. OS is Windows 11 Pro Version 10.0.26100.

The deploy results in the following error:

DEP0700: Registration of the app failed. [0x80073CF6] Error 0x80080204: The package "617e6418-6847-4fa1-bec6-3a3668d09f6d_1.0.0.0_x86__g0j7nbxh9a4mw" cannot be registered due to the following error: The appx package manifest is invalid. 

I need help for understanding this issue, because i have no more information about the problem. Hopy you folks can help. THX

I have a simple blank UWP application project with the following Package.appxmanifest

<?xml version="1.0" encoding="utf-8"?>
<Package
  xmlns="http://schemas.microsoft.com/appx/manifest/foundation/windows10"
  xmlns:mp="http://schemas.microsoft.com/appx/2014/phone/manifest"
  xmlns:uap="http://schemas.microsoft.com/appx/manifest/uap/windows10"
  xmlns:uap11="http://schemas.microsoft.com/appx/manifest/uap/windows10/11"
  xmlns:printsupport="http://schemas.microsoft.com/appx/manifest/printsupport/windows10"
  xmlns:printsupport2="http://schemas.microsoft.com/appx/manifest/printsupport/windows10/2"
  IgnorableNamespaces="uap mp printsupport printsupport2 uap11">

    <Identity
      Name="617e6418-6847-4fa1-bec6-3a3668d09f6d"
      Publisher="CN=patrick"
      Version="1.0.0.0" />

    <mp:PhoneIdentity
      PhoneProductId="617e6418-6847-4fa1-bec6-3a3668d09f6d"
      PhonePublisherId="00000000-0000-0000-0000-000000000000" />

    <Properties>
        <DisplayName>PrintingApp</DisplayName>
        <PublisherDisplayName>patrick</PublisherDisplayName>
        <Logo>Assets\StoreLogo.png</Logo>
    </Properties>

    <Dependencies>
        <TargetDeviceFamily Name="Windows.Universal"
            MinVersion="10.0.22000.0" MaxVersionTested="10.0.22621.0" />
    </Dependencies>

    <Resources>
        <Resource Language="x-generate" />
    </Resources>

    <Applications>
        <Application
          Id="App"
          Executable="$targetnametoken$.exe"
          EntryPoint="PrintingApp.App">
            <uap:VisualElements
              DisplayName="PrintingApp"
              Square150x150Logo="Assets\Square150x150Logo.png"
              Square44x44Logo="Assets\Square44x44Logo.png"
              Description="PrintingApp"
              BackgroundColor="transparent">
                <uap:DefaultTile Wide310x150Logo="Assets\Wide310x150Logo.png" />
                <uap:SplashScreen Image="Assets\SplashScreen.png" />
            </uap:VisualElements>

            <Extensions>
                 <!--1. Virtueller Drucker-Workflow--> 
                <printsupport2:Extension
                  Category="windows.printSupportVirtualPrinterWorkflow"
                  EntryPoint="PrintingApp.Tasks.PrintSupportWorkflowBackgroundTask"
                  uap11:SupportsMultipleInstances="true">
                    <printsupport2:PrintSupportVirtualPrinter
                      DisplayName="ms-resource://PRINTER_NAME1"
                      PrinterUri="contoso-psa:printer1"
                      PreferredInputFormat="application/postscript"
                      OutputFileTypes="ps;pdf"
                      PdcFile="Config\PRINTER_PDC1.xml">
                        <printsupport2:SupportedFormats>
                            <printsupport2:SupportedFormat Type="application/postscript" />
                            <printsupport2:SupportedFormat Type="application/pdf" MaxVersion="1.7" />
                        </printsupport2:SupportedFormats>
                    </printsupport2:PrintSupportVirtualPrinter>
                </printsupport2:Extension>

                 <!--2. Print-Support-Extension--> 
                <printsupport:Extension
                  Category="windows.printSupportExtension"
                  EntryPoint="PrintingApp.Tasks.PrintSupportExtensionBackgroundTask"
                  uap11:SupportsMultipleInstances="true" />

                 <!--3. Print-Support-SettingsUI--> 
                <printsupport:Extension
                  Category="windows.printSupportSettingsUI"
                  EntryPoint="PrintingApp.Tasks.PrintSupportSettingsUIBackgroundTask"
                  uap11:SupportsMultipleInstances="true" />

                 <!--4. Print-Support-JobUI--> 
                <printsupport:Extension
                  Category="windows.printSupportJobUI"
                  EntryPoint="PrintingApp.Tasks.PrintSupportJobUIBackgroundTask"
                  uap11:SupportsMultipleInstances="true" />
            </Extensions>
        </Application>
    </Applications>

    <Capabilities>
        <Capability Name="internetClient" />
    </Capabilities>
</Package>

The Entry Point classes are within the defined namespace and declared as public sealed partial class, e.g.

using Windows.ApplicationModel.Background;
using Windows.Graphics.Printing.PrintSupport;

namespace PrintingApp.Tasks
{
    /// <summary>
    /// Background-Task für PrintTicket-Validierung und -Erweiterungen.
    /// </summary>
    public sealed partial class PrintSupportExtensionBackgroundTask : IBackgroundTask
    {
        public void Run(IBackgroundTaskInstance taskInstance)
        {
            var deferral = taskInstance.GetDeferral();


            deferral.Complete();
        }
    }
}

Note that the PRINTER_PDC1 is of type content and copied always with this "dummy" content:

<?xml version="1.0" encoding="UTF-8"?>
<!--
  Beispiel einer PDC (Print Device Capabilities) für einen virtuellen Drucker (PSA).
  Namespace psk steht hier für das PrintSchemaKernel (siehe Schema-Definitionen).
-->
<psk:PrintDeviceCapabilities
    xmlns:psk="http://schemas.microsoft.com/windows/2003/08/printing/printschemakernel"
    psk:Version="1.0">

    <!-- Feature: PageMediaSize (Papierformat) -->
    <psk:Feature psk:Name="PageMediaSize">
        <psk:Option psk:Name="ISOA4">
            <psk:DisplayName xml:lang="en">A4</psk:DisplayName>
        </psk:Option>
        <psk:Option psk:Name="ISOB5">
            <psk:DisplayName xml:lang="en">B5</psk:DisplayName>
        </psk:Option>
        <psk:Option psk:Name="Letter">
            <psk:DisplayName xml:lang="en">Letter</psk:DisplayName>
        </psk:Option>
    </psk:Feature>

    <!-- Feature: PageOrientation (Ausrichtung) -->
    <psk:Feature psk:Name="PageOrientation">
        <psk:Option psk:Name="Portrait">
            <psk:DisplayName xml:lang="en">Hochformat</psk:DisplayName>
        </psk:Option>
        <psk:Option psk:Name="Landscape">
            <psk:DisplayName xml:lang="en">Querformat</psk:DisplayName>
        </psk:Option>
    </psk:Feature>

    <!-- Feature: PageOutputColor (Farbausgabe) -->
    <psk:Feature psk:Name="PageOutputColor">
        <psk:Option psk:Name="Color">
            <psk:DisplayName xml:lang="en">Farbe</psk:DisplayName>
        </psk:Option>
        <psk:Option psk:Name="Monochrome">
            <psk:DisplayName xml:lang="en">Schwarzweiß</psk:DisplayName>
        </psk:Option>
    </psk:Feature>

    <!-- Feature: Duplex (Beidseitig drucken) -->
    <psk:Feature psk:Name="Duplex">
        <psk:Option psk:Name="OneSided">
            <psk:DisplayName xml:lang="en">Einseitig</psk:DisplayName>
        </psk:Option>
        <psk:Option psk:Name="TwoSidedLongEdge">
            <psk:DisplayName xml:lang="en">Beidseitig (lange Kante)</psk:DisplayName>
        </psk:Option>
        <psk:Option psk:Name="TwoSidedShortEdge">
            <psk:DisplayName xml:lang="en">Beidseitig (kurze Kante)</psk:DisplayName>
        </psk:Option>
    </psk:Feature>

    <!-- Feature: Copies (Anzahl Kopien) -->
    <psk:Feature psk:Name="Copies">
        <psk:Option psk:Name="CopiesSupported"/>
    </psk:Feature>

</psk:PrintDeviceCapabilities>