This chapter has examined the way a managed COM add-in can be created using Visual Studio. You also learned how a managed COM add-in is registered in the registry, and the pitfalls of mscoree.dll for loading a managed COM add-in. To solve the problems with mscoree.dll, we recommended using a shim DLL to load a managed COM add-in. If you are building a COM add-in for Outlook 2003, there is a much better story for add-in developmentthe VSTO Outlook Add-in project described in Chapter 24.