[2008] Office add-in issue

[mattwise40175]

I am creating an office 2007 add-in for word and everything appears to work fine when I run it from debug mode. Once I create a setup and install it on another system and try to add the add-in into word i get the following error:

"PATH_TO_DLL" is not a valid Office Add-in.

Is there a special way to make a setup for an Office add-in that I am missing?

Thanks.