Found the answer How to Debug an office 2007-addin with office 2010
Basically on the project properties you have to go to debug and tell it to open outlook as the external program.
Question
I have a C# Outlook plugin and I'm using Visual Studio 2012. Whenever I try to debug against Outlook 2010 I get the following error: You cannot run or debug this project, because the required version of the microsoft office is not installed.
I had the same issue with Office 2013 but that was fixed by installing the Office Tools for Visual Studio 2012. Is there something I need to install to get it to work with Office 2010?
Thanks.
Solution
Found the answer How to Debug an office 2007-addin with office 2010
Basically on the project properties you have to go to debug and tell it to open outlook as the external program.