Hi I get this error message when trying to open a new sdlxliff file. I have uninstalled Trados and re-installed but the problem persists. I have deactivated my Norton firewall and antivirus but still the same problem. I clicked on the floppy disk at the bottom and here is what was written:

<SDLErrorDetails time="10/09/2018 17:26:01">

<ErrorMessage>La référence d'objet n'est pas définie à une instance d'un objet.</ErrorMessage>
<Exception>
<Type>System.NullReferenceException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</Type>
<HelpLink />
<Source>Sdl.ProjectApi.Helpers</Source>
<HResult>-2147467261</HResult>
<StackTrace><![CDATA[ à Sdl.ProjectApi.Helpers.LanguageDirectionHelper.GetCascadeSettings(ILanguageDirection languageDirection)
à Sdl.ProjectApi.Helpers.LanguageDirectionHelper.CreateCascade(ILanguageDirection languageDirection, ProjectCascadeEntryDataFilterFunction filter, IComparer`1 sort, Boolean readOnly, Boolean refreshCache)
à Sdl.TranslationStudio.Editor.TranslationEditor.TranslatableDocumentConfirmationStatistics..ctor(TranslatableDocument document, IMultiFileConverter converter)
à Sdl.TranslationStudio.Editor.TranslationEditor.TranslatableDocument.Load(IJobExecutionContext context)
à Sdl.Desktop.Platform.Services.JobRequest.Execute(IJobExecutionContext context)
à Sdl.Desktop.Platform.Implementation.Services.Job.<_worker_DoWork>b__3()
à Sdl.Desktop.Platform.Implementation.Services.Log.Resources(Object message, Action action)
à Sdl.Desktop.Platform.Implementation.Services.Job._worker_DoWork(Object sender, DoWorkEventArgs e)
à System.ComponentModel.BackgroundWorker.OnDoWork(DoWorkEventArgs e)
à System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument)]]></StackTrace>
</Exception>
<Environment>
<ProductName>SDL Trados Studio</ProductName>
<ProductVersion>12.0.0.0</ProductVersion>
<EntryAssemblyFileVersion>12.3.5281.10</EntryAssemblyFileVersion>
<OperatingSystem>Microsoft Windows 10 Famille</OperatingSystem>
<ServicePack>NULL</ServicePack>
<OperatingSystemLanguage>1036</OperatingSystemLanguage>
<CodePage>1252</CodePage>
<LoggedOnUser>LAPTOP-TPGFGLGT\adeli</LoggedOnUser>
<DotNetFrameWork>4.0.30319.42000</DotNetFrameWork>
<ComputerName>LAPTOP-TPGFGLGT</ComputerName>
<ConnectedToNetwork>True</ConnectedToNetwork>
<PhysicalMemory>4065180 MB</PhysicalMemory>
</Environment>
</SDLErrorDetails>