Make version-independent add-in for
Office 2021 - 2000 in Visual Studio: VB.NET, C#

Add-in Express™
for Microsoft® Office and .net

Your Office extensions are version-neutral

The Add-in Express core is specially designed to make your Microsoft Office solutions truly version-independent.

Unlike VSTO, you do not need to create multiple version-specific projects in order to support different versions of Microsoft Office. With Add-in Express you can write your code once and it will work on all versions, from Office 2000 to Office 2021/365.

Creating a version-neutral Office add-in is as simple as selecting the minimum version of Office you want to support on the Add-in Express New COM Add-in project creation wizard.

Creating a version neutral COM add-in for Microsoft Office

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Your Office solutions are shared

Version-independence is not the only benefit you get with Add-in Express. It enables you to write one codebase that supports not only all versions of Microsoft Office but also all the different applications installed on a user's machine. This means you do not need to create multiple projects to support different apps in the Office suite, making maintaining your code much easier and giving your users one setup program.

You only need to select the Microsoft Office application you want your add-in to support.

Select the Office applications supported by your add-in

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All pitfalls are bypassed

As new releases and service packs for Microsoft Office is released, it is an inevitable fact that some bugs can be introduced and can cause headaches for Microsoft Office developers.

Add-in Express is tested on all versions from 2000 to 2021 to get around all the known pitfalls that you might face when developing for Microsoft Office. This is to give you the confidence that your add-in will work on all your customers' PCs.

Supports all Microsoft Office suites, from Student to Enterprise

By using Add-in Express you can increase the installation base of your Microsoft Office extensions. Add-in Express supports all Microsoft Office suites, from Student and Home to Professional and Enterprise.

Works in all editions of Visual Studio, including Community and Express

Add-in Express works on all editions of Visual Studio, including Visual Studio Community and Express. You can develop feature rich extension for Microsoft Office using Visual Basic .NET (VB .NET), Visual C#, and Visual C++.
See Also