Developing Office add-ins in VSTO with C#, VB.NET
Add menu items, handle events, intercept shortcuts

Add-in Express™
for Microsoft® Office and VSTO

Never write code that has already been written

Real experience in Microsoft Office development

More than 60% of Add-in Express for VSTO source code has been developed to overcome pitfalls and unpleasant features of different Office versions and updates. Add-in Express is tested on all Office versions with all updates. It is used by thousands of programmers worldwide. With Add-in Express for VSTO you get our long-term practical experience in Office development.

Fact #1: Developer comfort

  • you use designers instead of coding

Other 40% of Add-in Express source code gives you speed, effectiveness and pleasure of Office add-in development. You use habitual Visual Studio design-time instruments to create add-ins, to create custom command bars, to add control onto custom or built-in toolbars, to add menu items, options pages and folder properties pages.

Fact #2: True RAD modules and project-specific components

  • you use designers instead of coding

Add-in Express for VSTO builds its project over special designers and components that allow you to create addins without coding their GUI. Add-in Express does all work behind the scene, you concentrate your efforts on the applied code only.

Fact #3: Office add-ins and add-in modules

  • you use designers instead of coding

All add-in projects include a special module (AddinModule) that implements the IDTExtensibility2 interface, provides access to objects and events of the add-in's host applications, contains GUI components and centralizes your applied code. The add-in module has designer of its own, where you place commandbars.

Fact #4: Ribbon user interface

  • you use designers instead of coding

Add-in Express provides a handy treeview-like design-time editor that allows creating custom Ribbon tabs, Office Menu items, and Quick Access Toolbar items. You will not have to generate and check the XML markup required by the programming interface provided by Microsoft. All this is done by the Add-in Express components automatically.

Fact #5: Command bars and controls

  • you use designers instead of coding

Add-in Express command bar components provide the easiest and most flexible way to create your custom controls on new or existing toolbars or menu bars, to replace any built-in toolbars with your own ones, to place your controls and any built-in controls side by side on your toolbars, menus and context menus. Moreover, all command bar components and controls take into account all pitfalls and features of Outlook command bars as well as multi-explorer and multi-inspector mode, which is native for Outlook. So, you develop add-ins GUI more quickly than ever before.

Fact #6: Hooking and hacking

  • you use designers instead of coding

Using a special component you can embed your code into event handlers of the built-in controls such as the Send button in Outlook, the Save menu item in Word, the Find command in Excel, etc. In addition, you can disable standard event handlers and completely replace them with your own ones.

Fact #7: Real keyboard shortcuts in all Office applications

  • you use designers instead of coding

Add-in Express allows you to intercept any keyboard shortcuts and use them for your custom controls. Now with command bar components and keyboard shortcuts you can completely substitute any built-in controls with custom ones, e.g. the Save and SaveAs commands to store Office documents in your document management system.

Fact #8: Event helpers

  • you use designers instead of coding

Add-in Express provides the easiest way to handle application-level events of the add-in's host applications. With event-helper components you can handle all events of all MS Office applications supported by Add-in Express. For example, you can handle the NewMail, NewExplorer, InspectorActivate events of Outlook, the WorkbookBeforeSave event of Excel, the DocumentOpen event of Word, etc.

Fact #9: Advanced Outlook features

  • you use designers instead of coding

Add-in Express for VSTO has a lot of advanced features for Outlook add-ins. Here are some of them: the support of the multi-explorer and multi-inspector modes, trusted add-ins, option pages for the main Outlook Options dialog and property pages for the Folder Properties dialog, Outlook Explorer- and Outlook Inspector-specific command bars that can be shown or enabled for selected folders only, several Outlook-specific event-helpers that help you to handle all Outlook events.


  • Stop coding things that have already been coded!

Add-in Express for VSTO is a time-saving toolkit the mail purpose of which is to give you more time for concentrating on your work instead of coding things that have already been coded many times by many people.