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2007 Microsoft Office Add-in Project Templates

Note Required applications

The features in this topic are available only if you have the required applications installed.

For more information, see Features Available by Product Combination.

  • One of these development environments:

    VSTO 2005


    Visual Studio Team System


    Visual Studio 2005 Professional Edition

  • VSTO 2005 SE installed in the development environment

  • 2007 Microsoft Office system

Add-in project templates for the 2007 Microsoft Office system automatically add the necessary project references, files, and basic code to use as a starting point for application-level add-ins for the following applications:

  • Microsoft Office Excel 2007

  • Microsoft Office InfoPath 2007

  • Microsoft Office Outlook 2007

  • Microsoft Office PowerPoint 2007

  • Microsoft Office Visio 2007

  • Microsoft Office Word 2007

For more information about application-level add-ins, see Office Solutions Architecture Overview.


By default, some of the files and references in the following list are hidden. To see them, click Show All Files on the Solution Explorer toolbar. Additionally, there are some files and references not in the following list that are common to many Visual Studio project templates.

The following methods are included in the project template code file.

Startup (ThisAddIn_Startup)

This method handles the Startup event, which is raised after the application is running and all the initialization code in the assembly has been run. It is the last thing to run in the constructor of the class that your code is running in.

Shutdown (ThisAddIn_Shutdown)

This method handles the Shutdown event, which is raised when the application domain that your code is loaded in is about to unload. It is the last thing to be called in the class as it unloads.

By default, one user file is visible:

  • ThisAddIn (.vb file for Visual Basic or .cs file for Visual C#) - The main code file for the add-in.

Hidden Files

Microsoft Visual Studio 2005 Tools for the Microsoft Office System generates these hidden files. Do not modify these files manually; they are regenerated when changes are made to the project and they do not retain manual modifications.

  • ThisAddIn.Designer.xml - A declarative representation of the programmable objects in the add-in project.

  • ThisAddIn.Designer (.vb file for Visual Basic or .cs file for Visual C#) - A code file that provides helper implementations. These include code to instantiate objects correctly.

Visual Studio Tools for Office automatically creates a set of assembly references in add-in projects. Some references are shared by all add-in project types, and others are unique to specific projects. The following table describes the assembly references.

Assembly reference Project type Description



The primary interop assembly for shared Office components.



An assembly that provides the AddIn base class for the add-in.



A collection of classes for developing task pane solutions.



The component that loads the main add-in assembly.



The primary interop assembly for Automation.

Various .NET Framework assemblies


A collection of references to some of the .NET Framework assemblies that are used when you develop Visual Studio Tools for Office solutions.


Excel Add-in

An assembly that provides the ExcelLocale1033Proxy and ExcelLocale1033Attribute classes. Excel add-ins can use these classes to pass the locale ID (LCID) 1033 to Excel for all culture-sensitive calls to the Excel object model. For more information, see Formatting Data in Excel with Various Regional Settings.


Excel Add-in

The primary interop assembly for Excel.


InfoPath Add-in

The primary interop assembly for InfoPath.


Outlook Add-in

The primary interop assembly for Outlook.


PowerPoint Add-in

The primary interop assembly for PowerPoint.


Visio Add-in

The primary interop assembly for Visio.


Word Add-in

The primary interop assembly for Word.