TranslationMemoryImporter throws error when trying to import TMX file

I'm trying to create a TM Batch Import Tool according to the information provided here:

https://developers.rws.com/studio-api-docs/apiconcepts/translationmemory/introduction_to_the_tm_batch_import_tool.html

After some troubleshooting because of missing information and some small errors in the code I can run the TM Import tool. However, the following line in the TmImporter.cs class produces an error:

importer.Import(tmxPath);

Here is the error message:

Sdl.LanguagePlatform.Core.LanguagePlatformException: Die angeforderte Datendatei kann nicht gefunden werden.
   bei Sdl.LanguagePlatform.TranslationMemoryApi.AbstractLocalTranslationMemory.get_Setup()
   bei Sdl.LanguagePlatform.TranslationMemoryApi.FileBasedTranslationMemoryLanguageDirection.get_SourceLanguage()
   bei Sdl.LanguagePlatform.TranslationMemoryApi.TranslationMemoryLanguageDirectionImportExport.get_SourceLanguage()
   bei Sdl.Core.TM.ImportExport.Importer.CreateTmxReaderSettings()
   bei Sdl.Core.TM.ImportExport.Importer.ImportTmxFile(String fileName)
   bei Sdl.Core.TM.ImportExport.Importer.Import(String fileName, IImportDestination importDestination)
   bei Sdl.LanguagePlatform.TranslationMemoryApi.TranslationMemoryImporter.Import(String fileName)
   bei TMXimporttool.TmImporter.Import(String tmxPath)

Here is a sample from the TMX file:

<?xml version="1.0" encoding="utf-8"?>
<tmx version="1.4">
  <header creationtool="SDL Language Platform" creationtoolversion="8.1" o-tmf="SDL TM8 Format" datatype="xml" segtype="sentence" adminlang="de-DE" srclang="de-DE" creationdate="20210525T060522Z" creationid="liNac\sbr">
    <prop type="x-Quality:Integer"></prop>
    <prop type="x-SourceFile:SingleString"></prop>
    <prop type="x-TargetFile:SingleString"></prop>
    <prop type="x-Recognizers">RecognizeDates, RecognizeTimes, RecognizeNumbers, RecognizeAcronyms, RecognizeVariables, RecognizeMeasurements</prop>
    <prop type="x-IncludesContextContent">True</prop>
    <prop type="x-TMName">de-DE_en-US</prop>
    <prop type="x-TokenizerFlags">DefaultFlags</prop>
    <prop type="x-WordCountFlags">DefaultFlags</prop>
  </header>
  <body>
    <tu creationdate="20180808T123940Z" creationid="liNac\jen" changedate="20180808T123940Z" changeid="liNac\jen" lastusagedate="20180808T123940Z">
      <prop type="x-LastUsedBy">liNac\jen</prop>
      <prop type="x-Origin">Alignment</prop>
      <prop type="x-ConfirmationLevel">ApprovedSignOff</prop>
      <prop type="x-SourceFile:SingleString">PA01Projektverwaltung2017_02_22_okJEN_AW01ProjectAdministration2016_08_19_okCB.sdlalign</prop>
      <prop type="x-TargetFile:SingleString">PA01Projektverwaltung2017_02_22_okJEN_AW01ProjectAdministration2016_08_19_okCB.sdlalign</prop>
      <prop type="x-Quality:Integer">100</prop>
      <tuv xml:lang="de-DE">
        <seg>Seite <ph type="441" />    Praktisches Arbeiten</seg>
      </tuv>
      <tuv xml:lang="en-US">
        <seg>Page <ph type="442" />    Applied Working</seg>
      </tuv>
    </tu>


Can you look into this and tell me if there is any mistake? For reference, please look at the RWS developers page (link see above).
Additional not: I coded everything exactly like on the RWS API developer page.


Added info on where code was retrieved.
[edited by: Matthias Burbank at 2:22 PM (GMT 0) on 16 Jan 2024]