Office Primary Interop Assemblies
When you create a new Visual Studio Tools for Office project, a reference to the correct primary interop assembly (PIA) is added to your project automatically if the assembly is installed in the Windows global assembly cache (GAC). The Microsoft Office primary interop assemblies are installed in the global assembly cache during a Complete installation.
For more information about primary interop assemblies, see Primary Interop Assemblies and the MSDN article "Primary Interop Assemblies (PIAs)" (http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dndotnet/html/whypriinterop.asp).


For Microsoft Office applications that do not have projects in Visual Studio Tools for Office, you must add a reference to the appropriate application or component to your project manually. Adding a reference to the component references the primary interop assembly, if the assembly is installed in the global assembly cache. Office applications and components are accessible from the COM tab of the Add Reference dialog box.
If the primary interop assembly is not installed in the global assembly cache, Visual Studio generates an interop assembly for the project that might not work fully in all cases. For more information, see Troubleshooting in Office at Run Time.
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Some assemblies are added to a project automatically when an assembly that references them is added. For example, references to the assemblies Office.dll and Microsoft.Vbe.Interop.dll are added automatically when you add a reference to the Word, Excel, Outlook, Microsoft Forms, or Graph assemblies. |
For more information about installing Office primary interop assemblies, see How to: Install Office Primary Interop Assemblies. For more information about adding references, see How to: Add and Remove References in Visual Studio (C#, J#).


The following table shows primary interop assemblies that are available to install with Microsoft Office 2003.
Office Application or Component | Primary Interop Assembly Name |
---|---|
Microsoft Access 11.0 Object Library |
Microsoft.Office.Interop.Access.dll |
Microsoft Excel 11.0 Object Library |
Microsoft.Office.Interop.Excel.dll |
Microsoft FrontPage 6.0 Web Object Reference Library |
Microsoft.Office.Interop.Frontpage.dll |
Microsoft FrontPage 6.0 Page Object Reference Library |
Microsoft.Office.Interop.Frontpageeditor.dll |
Microsoft Graph 11.0 Object Library (used by PowerPoint, Access, and Word for graphs) |
Microsoft.Office.Interop.Graph.dll |
Microsoft Outlook 11.0 Object Library |
Microsoft.Office.Interop.Outlook.dll |
Microsoft Outlook View Control (can be used in Web pages and applications to access your Inbox) |
Microsoft.Office.Interop.OutlookViewCtl.dll |
Microsoft Office Web Components 11.0 (spreadsheet, graph, and pivot table for Web pages) |
Microsoft.Office.Interop.owc11.dll |
Microsoft PowerPoint 11.0 Object Library |
Microsoft.Office.Interop.PowerPoint.dll |
Microsoft Publisher 11.0 Object Library |
Microsoft.Office.Interop.Publisher.dll |
Microsoft Smart Tags 2.0 Type Library |
Microsoft.Office.Interop.SmartTag.dll |
Microsoft Word 11.0 Object Library |
Microsoft.Office.Interop.Word.dll |
Microsoft Visual Basic for Applications Extensibility 5.3 |
Microsoft.Vbe.Interop.dll |
Microsoft Forms 2.0 Object Library (programmable controls that can be used in applications) |
Microsoft.Vbe.Interop.Forms.dll |
Microsoft Office 11.0 Object Library (Office shared functionality) |
office.dll |


The following table shows primary interop assemblies that are available to install with the 2007 Microsoft Office system.
Office Application or Component | Primary Interop Assembly Name |
---|---|
Microsoft Access 12.0 Object Library |
Microsoft.Office.Interop.Access.dll |
Microsoft Office 2007 Access database engine Object Library |
Microsoft.Office.Interop.Access.Dao.dll |
Microsoft Excel 12.0 Object Library |
Microsoft.Office.Interop.Excel.dll |
Microsoft Graph 12.0 Object Library (used by PowerPoint, Access, and Word for graphs) |
Microsoft.Office.Interop.Graph.dll |
Microsoft InfoPath 2.0 Type Library |
Microsoft.Office.Interop.InfoPath.dll |
Microsoft InfoPath XML Interop Assembly |
Microsoft.Office.Interop.InfoPath.Xml.dll |
Microsoft Outlook 12.0 Object Library |
Microsoft.Office.Interop.Outlook.dll |
Microsoft Office Outlook View Control (can be used in Web pages and applications to access your Inbox) |
Microsoft.Office.Interop.OutlookViewCtl.dll |
Microsoft PowerPoint 12.0 Object Library |
Microsoft.Office.Interop.PowerPoint.dll |
Microsoft Publisher 12.0 Object Library |
Microsoft.Office.Interop.Publisher.dll |
Microsoft SharePointDesigner 12.0 Web Object Reference Library |
Microsoft.Office.Interop.SharePointDesigner.dll |
Microsoft SharePointDesigner 12.0 Page Object Reference Library |
Microsoft.Office.Interop.SharePointDesignerPage.dll |
Microsoft Smart Tags 2.0 Type Library |
Microsoft.Office.Interop.SmartTag.dll |
Microsoft Visio 12.0 Type Library |
Microsoft.Office.Interop.Visio.dll |
Microsoft Visio 12.0 Save As Web Type Library |
Microsoft.Office.Interop.Visio.SaveAsWeb.dll |
Microsoft Visio 12.0 Drawing Control Type Library |
Microsoft.Office.Interop.VisOcx.dll |
Microsoft Word 12.0 Object Library |
Microsoft.Office.Interop.Word.dll |
Microsoft Visual Basic for Applications Extensibility 5.3 |
Microsoft.Vbe.Interop.dll |
Microsoft Office 12.0 Object Library (Office shared functionality) |
office.dll |
Binding Redirect Assembly for Microsoft Access Object Library |
Policy.11.0.Microsoft.Office.Interop.Access.dll |
Binding Redirect Assembly for Microsoft Excel Object Library |
Policy.11.0.Microsoft.Office.Interop.Excel.dll |
Binding Redirect Assembly for Microsoft Graph Object Library |
Policy.11.0.Microsoft.Office.Interop.Graph.dll |
Binding Redirect Assembly for Microsoft InfoPath Type Library |
Policy.11.0.Microsoft.Office.Interop.InfoPath.dll |
Binding Redirect Assembly for Microsoft InfoPath XML Interop Assembly |
Policy.11.0.Microsoft.Office.Interop.InfoPath.Xml.dll |
Binding Redirect Assembly for Microsoft Outlook Object Library |
Policy.11.0.Microsoft.Office.Interop.Outlook.dll |
Binding Redirect Assembly for Microsoft Outlook View Control |
Policy.11.0.Microsoft.Office.Interop.OutlookViewCtl.dll |
Binding Redirect Assembly for Microsoft PowerPoint Object Library |
Policy.11.0.Microsoft.Office.Interop.PowerPoint.dll |
Binding Redirect Assembly for Microsoft Publisher Object Library |
Policy.11.0.Microsoft.Office.Interop.Publisher.dll |
Binding Redirect Assembly for Microsoft Smart Tags Type Library |
Policy.11.0.Microsoft.Office.Interop.SmartTag.dll |
Microsoft Visio Type Library |
Policy.11.0.Microsoft.Office.Interop.Visio.dll |
Binding Redirect Assembly for Microsoft Visio Save As Web Type Library |
Policy.11.0.Microsoft.Office.Interop.Visio.SaveAsWeb.dll |
Binding Redirect Assembly for Microsoft Visio Drawing Control Type Library |
Policy.11.0.Microsoft.Office.Interop.VisOcx.dll |
Binding Redirect Assembly for Microsoft Word Object Library |
Policy.11.0.Microsoft.Office.Interop.Word.dll |
Binding Redirect Assembly for Microsoft Visual Basic for Applications Extensibility 5.3 |
Policy.11.0.Microsoft.Vbe.Interop.dll |
Binding Redirect Assembly for Microsoft Office Object Library |
Policy.11.0.office.dll |
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The binding redirect assemblies help make sure that the 2007 Microsoft Office version of the primary interop assemblies are loaded at run time. When a Visual Studio Tools for Office solution that references a Microsoft Office 2003 primary interop assembly runs on a computer that has the 2007 Microsoft Office version of the same primary interop assembly, the binding redirect assembly instructs the .NET Framework runtime to load the 2007 Microsoft Office version of the primary interop assembly. For more information, see Assembly Binding Redirection. From:http://msdn.microsoft.com/en-us/library/15s06t57(VS.80).aspx |
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