Program Error (Server Error 500)

<h1>Program Error (Server Error 500)</h1>
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             <p>
              <em>
              More information about this error may be available in the 
              server error log and/or program error log. 
              </em>
             </p>
             <hr />
               <pre>Dada Mail 3.0.3 Stable error, please MAKE SURE that '/mnt/www/newsletter_liste/liste_newsletter' is a directory (NOT a file) and that Dada Mail has enough permissions to write into this directory: No such file or directory at DADA/App/Subscriptions.pm line 908
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