Thank you very much Viv.

I have reasons to be believe that the Clipboard data are there, as I can manually copy them after the program executed.

The Clipboard Class specs are certainly worth a read. Who thought there was more to it than just Control C and Control V ? :)

>Can't test - haven't got word on this machine.
>
>It could be that the clipboard data is cleared when the ExcelWrapper is disposed ?
>You can use the Clipboard class ( https://msdn.microsoft.com/en-us/library/system.windows.forms.clipboard(v=vs.110).aspx ) to check the content of the clipboard.
>If it IS being cleared then instead of the Range.Copy() you might be able to also use the ClipBoard.SetData(object, Boolean) method to persist the data on the clipboard. Never tried it but.......
>
>>>Actual code might be useful......
>>
>>Sure. Enjoy, if that's the word :)
>>
>>This was the problem:
>>>>I prepare a table in Excel within a Using () statement. At the end I UsedRange.Copy() to what I understand is the clipboard. Then I Selection.PasteExcelTable in a Word document.
>>>>I get an COM Exception "command failed".
>>>>When I activate the word document and press Ctrl+V the table gets copied.
>>>>I wonder if that has something to do with the fact that maybe I must reactivate the Word document in code.
>>>>The word document gets created also within a Using() statement. I execute the Excel procedure from within the Using(Word) statement.
>>>>
>>>>I tried the Activate method of the Word.Application object and also when I wait for 5 seconds after the Activate().
>>
>>
>>The method that opens Word. Test_ComputeTotalDifference() is a method that calls Excel (see below). AddClopboard (see below) is the statement that breaks.
>>

>>        public static void Test_Word()
>>        {
>>            Test_ComputeTotalDifference();
>>            using (var w = new WordWrapper())
>>            {
>>                w.App.Visible = true;
>>                w.Doc = w.Docs.Add();
>>                w.Sel = w.App.Selection;
>>                w.SetNarrowMargins();
>>                w.Title("Inventory Monitor (PIMON)");
>>                w.Heading2("1. Overall Discrepancies");
>>                
>>                w.AddClipboard();
>>                w.Heading2("2. Carat Discrepancies");
>>                w.Doc.SaveAs(@"C:\docs\WordTest.docx");
>>            }
>>        }
>>

>>The code breaks here (a method of WordWrapper, see below
>>

>>       public void AddClipboard()
>>        {
>>            App.Activate();
>>            System.Threading.Thread.Sleep(5000);
>>            Sel.PasteExcelTable(false,false, false);
>>            var t = Sel.Tables[Sel.Tables.Count];
>>            t.Range.Select();           
>>            Sel.set_Style(App.ActiveDocument.Styles["No Spacing"]);
>>            t.AutoFitBehavior(Word.WdAutoFitBehavior.wdAutoFitContent);
>>            Doc.Paragraphs.Add().Range.Select();
>>            Sel.set_Style(App.ActiveDocument.Styles["No Spacing"]);
>>            Sel.TypeText("\n");
>>        }
>>

>>Here's the method that creates the excel sheet and copies it to the clipboard
>>

>>        public static void Test_ComputeTotalDifference()
>>        {
>>            Serialization.Deserialize();
>>            using (var xl = new ExcelWrapper())
>>            {
>>                xl.wb = xl.wbs.Add();
>>                xl.ws = xl.wb.ActiveSheet;
>>
>>... snip ...
>>                xl.ws.UsedRange.CopyPicture();
>>
>>            }
>>        }
>>

>>
>>Here's the excelwrapper class that gets initialized with a Using
>>

>>    public class ExcelWrapper : IDisposable
>>    {
>>        public enum Formats {decimal2,decimal0,date,text}
>>        public Excel.Application app;
>>        public Excel.Workbooks wbs;
>>        public Excel.Workbook wb;
>>        public Excel.Worksheets wss;
>>        public Excel.Worksheet ws;
>>        public Excel.Range rng;
>>        public bool mustQuit = true;
>>        CultureInfo originalCulture;
>>        Thread thread;
>>        
>>        bool disposed = false;
>>        #region "Dispose"
>>        public ExcelWrapper()
>>        {
>>            thread = Thread.CurrentThread;
>>            originalCulture = thread.CurrentCulture;
>>            app = new Excel.Application();
>>            app.DisplayAlerts = false;
>>            wbs = app.Workbooks;
>>        }
>>        void releaseObject(object o)
>>        {
>>            if (o == null) 
>>            {
>>                return;
>>            }
>>            System.Runtime.InteropServices.Marshal.FinalReleaseComObject(o);
>>        }
>>        public void Dispose() {
>>            if (disposed){
>>                return;
>>            }
>>            // try { wb.Close(); } finally { }
>>            if (mustQuit) {
>>                app.Quit();
>>            }
>>            releaseObject(rng);
>>            releaseObject(ws);
>>            releaseObject(wss);
>>            releaseObject(wb);
>>            releaseObject(wbs);
>>            thread.CurrentCulture = originalCulture;
>>            disposed = true;
>>        }
>>       ~ExcelWrapper()
>>        {   
>>        	Dispose();
>>        }
>>

>>Similarly here is the Wordwrapper.
>>

>>        public WordWrapper()
>>        {
>>            thread = Thread.CurrentThread;
>>            App = new Word.Application();
>>            App.DisplayAlerts = Microsoft.Office.Interop.Word.WdAlertLevel.wdAlertsNone;
>>            Docs = App.Documents;
>>        }
>>        void releaseObject(object o)
>>        {
>>            if (o == null)
>>            {
>>                return;
>>            }
>>            System.Runtime.InteropServices.Marshal.FinalReleaseComObject(o);
>>        }
>>        public void Dispose()
>>        {
>>            if (disposed)
>>            {
>>                return;
>>            }
>>            // try { wb.Close(); } finally { }
>>            if (MustQuit)
>>            {
>>                App.Quit();
>>            }
>>            releaseObject(Doc);
>>            releaseObject(Docs);
>>            disposed = true;
>>        }
>>        ~WordWrapper()
>>        {
>>            Dispose();
>>        }
>>