How to make version-independent add-in for
Office 2019 - 2000 in Visual Studio: VB.NET, C#
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 2019.
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.
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.
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 2019 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 Express
Add-in Express works on all editions of Visual Studio, including Visual Studio Express. You can develop feature rich extension for Microsoft Office using Visual Basic .NET (VB .NET), Visual C#, and Visual C++ in Visual Studio 2017, 2015, 2013, 2012 and 2010.