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Studio 2021 + DeepL - Error

Hi all,

A colleague of mine installed Studio 2021 and wanted to add the DeepL plugin.

Her Studio version is, and we just downloaded and installed the current plugin (version

The error message is:

<SDLErrorDetails time="07.09.2020 09:42:01">
  <ErrorMessage>Der Wert darf nicht NULL sein.
Parametername: source</ErrorMessage>
    <Type>System.ArgumentNullException, mscorlib, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089</Type>
    <HelpLink />
    <StackTrace><![CDATA[   bei System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source, Func`2 predicate)
   bei Sdl.Community.DeepLMTProvider.DeepLTranslationProviderConnecter.GetLanguage(CultureInfo culture, List`1 languageList)
   bei Sdl.Community.DeepLMTProvider.DeepLMtTranslationProvider.GetSupportedTargetLanguages(LanguagePair[] languagePairs)
   bei Sdl.Community.DeepLMTProvider.DeepLMtTranslationProviderWinFormsUI.Browse(IWin32Window owner, LanguagePair[] languagePairs, ITranslationProviderCredentialStore credentialStore)
   bei Sdl.TranslationStudio.Common.TranslationMemory.TranslationMemoriesControl.pluginContextMenuStripItem_Click(Object sender, EventArgs e)
   bei System.Windows.Forms.ToolStripItem.RaiseEvent(Object key, EventArgs e)
   bei System.Windows.Forms.ToolStripMenuItem.OnClick(EventArgs e)
   bei System.Windows.Forms.ToolStripItem.HandleClick(EventArgs e)
   bei System.Windows.Forms.ToolStripItem.HandleMouseUp(MouseEventArgs e)
   bei System.Windows.Forms.ToolStripItem.FireEventInteractive(EventArgs e, ToolStripItemEventType met)
   bei System.Windows.Forms.ToolStripItem.FireEvent(EventArgs e, ToolStripItemEventType met)
   bei System.Windows.Forms.ToolStrip.OnMouseUp(MouseEventArgs mea)
   bei System.Windows.Forms.ToolStripDropDown.OnMouseUp(MouseEventArgs mea)
   bei System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   bei System.Windows.Forms.Control.WndProc(Message& m)
   bei System.Windows.Forms.ScrollableControl.WndProc(Message& m)
   bei System.Windows.Forms.ToolStrip.WndProc(Message& m)
   bei System.Windows.Forms.ToolStripDropDown.WndProc(Message& m)
   bei System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   bei System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   bei System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)]]></StackTrace>
    <ProductName>SDL Trados Studio</ProductName>
    <OperatingSystem>Microsoft Windows 10 Home</OperatingSystem>
    <PhysicalMemory>8277272 MB</PhysicalMemory>

What could be wrong here?

Thanks for any help!


Annette (from Manfred's account)

  • Interestingly just reported the same error in another thread for 2019.  For your user, who just installed 2021 I would guess the problem is related to there being no language pairs available in Studio yet (and we need to fix this if it's the case), but I didn't think that would be the problem for Thilo as he's an existing 2019 user.

    Please try adding your language pairs here (if there aren't any) and then try again:

  • Greetings,

    Many thanks for this answer,

    I am currently experiencing the same problem, with a freshly installed Studio 2021. There was indeed no language pair in said window (surprisingly) so I added my usual ones. But to no avail.

    If this helps, these are the things I tried :

    - Adding a couple language pairs (EN-GB>FR, EN-US>FR and IT>FR) as said above. These are well supported by Deepl. Tried adding Deepl Translation Provider along with my TMs in my project properties. No luck.

    - Restarted Studio and tried adding again Deepl along with my TM.

    - Removing, restarting computer (and therefore Studio) than adding Deepl plugin (this time from the Appstore window built in Studio 2021)

    - Recreating my API key in my Deepl Pro account..

    None of these steps helped.

    As a Freelance Plus user, I have two activations, and I did not stumble upon this error a few days ago (28.08.20) when I installed Studio 2021 and this plugin on my other computer (laptop, similar environment : Windows 10 ed. 2004 up to date).

    I have a very similar error details message as the one posted by Manfred Altmann (of course except that my error reads as "La valeur ne peut pas être null, Nom du paramètre: Source" in French -my system language- and that the "environment" tags match my own computer environment).

    I may post my own error details should you judge it necessary, but mine is very similar.

    I'll stay tuned should you need more info.

    Thanks again,


  • Thanks

    We're investigating this at the moment.  I'll post back in here when we know more.

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