Today we release v2 of the COM Shim Wizards. These are updated versions of the wizards we released in 2004 for Visual Studio 2003. The new wizards work with Visual Studio 2005.

There's a covering article here:

You can download the wizards here:

These wizards allow you to build unmanaged shims for managed Office extensions, including shared add-ins, smart tags and realtime data servers. The wizards will ask you a few simple questions and then generate all the code for the shim, so that you only have to build the shim - you don't have to write any code.

The reasons why you should use a shim for managed Office add-ins and other extensions are detailed in the article, but essentially they increase robustness by isolating each extension in a separate appdomain. Of course, this functionality is one of the main advantages of using VSTO add-ins over shared add-ins, and is built into the VSTO runtime. Unfortunately, VSTO 2005 provided add-in support only for Outlook 2003. So if you're targeting any other Office 2003 application, or any earlier version of Office, you had no choice but to use shared add-ins.

The v2 wizards are basically the same as the v1 wizards, although we did take the opportunity to fix a bug and streamline the UI. The only significant difference is that the v2 shims support unloading of the target assemblies.

Until VSTO add-ins provide support for a wider range of Office applications (which it will in the upcoming releases), you are encouraged to provide shims for your add-ins, and these wizards do cover off this requirement quite nicely.