Version-neutral, bit-neutral Internet Explorer add-on for IE6,
IE7 and IE8 (32-bit and 64-bit) in VB.NET, C#, C++

Add-in Express™
for Internet Explorer® and Microsoft® .net

Version-neutrality - one your project works for IE6, IE7 and IE8

Add-in Express delivers version-neutral interop assemblies based on the Internet Explorer 6.0 type library. Using these assemblies you can program version-neutral Internet Explorer add-ons compatible with all popular IE versions including IE 6, 7 and 8. However, you can develop add-ons compatible with IE 7 and 8 only if you create an add-on solution on a PC with IE 7 installed - simply use the interop assemblies for the currently installed IE version. In this case, the interops will be generated and included in your solution automatically:

New Project Wizard for IE add-ons

Stop counting bits - all your add-ons are bit-neutral

By default, all your solutions based on Add-in Express are compiled for any CPU. So all your solutions are platform-neutral (or bit-neutral). However, to make your add-ons more secure and stable, Add-in Express isolates each of them in separate application domains by using a special Win32 "shim", the Add-in Express Loader. There are two versions of the loader, one for 32-bit and the other for the 64-bit CPU. Both versions are included in IE add-on setup projects and are separately registered for 32- and 64-bit versions of Internet Explorer. You don't need create special actions in your setup projects - all custom actions needed for add-on registration are generated automatically.

A new add-on project in the Solution window of Visual Studio