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procedure TfmUploader.btnStartClick(Sender: TObject);
begin
        btnStart.Caption:='Bitte warten...'; // Button-Caption
        Cursor:=crHourGlass; // Cursor setzen
        if odUpload.Execute then
        begin
                slText.LoadFromFile(odUpload.FileName); // <--- Hier ist das Problem!
                ShellExecute(Handle,'open',PChar('http://www.domain.net/php-script.php?param1='+odUpload.FileName+'¶m2='+slText.Text),'','',0);
        end;
        Cursor:=crDefault;
        btnStart.Caption:='Upload';
end;                    

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 slText:= TStringList.create;