exceldelphims-worddelphi-6

"Interface not supported" error when attempting to generate an Excel or Word document from Delphi 6

Years ago I’ve written a Delphi 6 application that uses OLE automation to generate content in Excel and Word. This code functioned correctly for years on older systems, but fails on my current Windows 10 machine with Office 2016 with the error "Interface not supported".

Environment: Delphi 6 Enterprise, Windows 10 Pro (Version 21H2), Microsoft Office Professional Plus 2016

My full code is too long to paste here verbatim so I’ve extracted a sample that’s sufficient to demonstrate a failure scenario. The error occurs when invoking the CreateOleObject line.

unit Unit1;

interface

uses
  Windows, ComObj, ActiveX, Variants, SysUtils, Dialogs;

procedure OpenExcelAndWordWithText;

implementation

procedure OpenExcelAndWordWithText;
var
  ExcelApp, Workbook, Worksheet: Variant;
  WordApp, Document: Variant;
begin
  CoInitialize(nil);
  
  try
    try
      ExcelApp := CreateOleObject('Excel.Application');
      ExcelApp.Visible := True;
      Workbook := ExcelApp.Workbooks.Add;
      Worksheet := Workbook.Worksheets[1];
      Worksheet.Cells[1, 1] := 'Hello world';
    except
      on E: Exception do
      begin
        ShowMessage('Excel Error: ' + E.Message);
        Exit;
      end;
    end;
    
    try
      WordApp := CreateOleObject('Word.Application');
      WordApp.Visible := True;
      Document := WordApp.Documents.Add;
      Document.Content.Text := 'Hello world';
    except
      on E: Exception do
        ShowMessage('Word Error: ' + E.Message);
    end;
  finally
    CoUninitialize;
  end;
end;

end.

How can I fix the issue?

Solution

  • The problem was that the previous version of Excel was uninstalled incorrectly on the machine. To fix it, I used the following instructions from Microsoft:

    1. Open the regedit editor.
    2. Open HKEY_CLASSES_ROOT >> TypeLib >> {00020813-0000-0000-C000-000000000046} (The Excel PIA key is {00020813-0000-0000-C000-000000000046})
    3. Delete the last version folder (Excel 2013 is 1.8, Excel 2016 is 1.9)

    A similar fix can be applied to other Office products:

    Excel
    HKEY_CLASSES_ROOT\TypeLib{00020813-0000-0000-C000-000000000046}\

    • 1.7 is for Office 2010
    • 1.8 is for Office 2013
    • 1.9 is for Office 2016

    Word
    HKEY_CLASSES_ROOT\TypeLib{00020905-0000-0000-C000-000000000046}\

    • 8.5 is for Office 2010
    • 8.6 is for Office 2013
    • 8.7 is for Office 2016

    PowerPoint
    HKEY_CLASSES_ROOT\TypeLib{91493440-5A91-11CF-8700-00AA0060263B}\

    • 2.a is for Office 2010
    • 2.b is for Office 2013
    • 2.c is for Office 2016

    Outlook
    HKEY_CLASSES_ROOT\TypeLib{00062FFF-0000-0000-C000-000000000046}\

    • 9.4 is for Office 2010
    • 9.5 is for Office 2013
    • 9.6 is for Office 2016

    Here's a sample regedit file to fix the Registry for Office 2016:

    Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\TypeLib\{00020813-0000-0000-C000-000000000046}\1.9]
"PrimaryInteropAssemblyName"="Microsoft.Office.Interop.Excel, Version=15.0.0.0, Culture=neutral, PublicKeyToken=71E9BCE111E9429C"
@="Microsoft Graph 16.0 Object Library"

[HKEY_CLASSES_ROOT\TypeLib\{00020813-0000-0000-C000-000000000046}\1.9\0]

[HKEY_CLASSES_ROOT\TypeLib\{00020813-0000-0000-C000-000000000046}\1.9\0\win64]
@="C:\\Program Files\\Microsoft Office\\Office16\\EXCEL.EXE"

[HKEY_CLASSES_ROOT\TypeLib\{00020813-0000-0000-C000-000000000046}\1.9\FLAGS]
@="0"

[HKEY_CLASSES_ROOT\TypeLib\{00020813-0000-0000-C000-000000000046}\1.9\HELPDIR]
@="C:\\Program Files\\Microsoft Office\\Office16\\"

[HKEY_CLASSES_ROOT\TypeLib\{00020905-0000-0000-C000-000000000046}\8.7]
"PrimaryInteropAssemblyName"="Microsoft.Office.Interop.Word, Version=15.0.0.0, Culture=neutral, PublicKeyToken=71E9BCE111E9429C"
@="Microsoft Graph 16.0 Object Library"

[HKEY_CLASSES_ROOT\TypeLib\{00020905-0000-0000-C000-000000000046}\8.7\0]

[HKEY_CLASSES_ROOT\TypeLib\{00020905-0000-0000-C000-000000000046}\8.7\0\win64]
@="C:\\Program Files\\Microsoft Office\\Office16\\MSWORD.OLB"

[HKEY_CLASSES_ROOT\TypeLib\{00020905-0000-0000-C000-000000000046}\8.7\FLAGS]
@="0"

[HKEY_CLASSES_ROOT\TypeLib\{00020905-0000-0000-C000-000000000046}\8.7\HELPDIR]
@="C:\\Program Files\\Microsoft Office\\Office16\\"