I have several Add-Ins that where created using ArcMap 10.0 and Visual Studio 2010. I’m trying to get them to work in ArcMap 10.2.1 using VS 2012. When I build the projects I’m getting the following message: "Unable to create .esriAddIn: missing ESRI ArcGIS Add-In SDK component(s)." As a result ArcMap is not “seeing” my Add-Ins. Is there something I can fix/change in my Add-Ins to get them to work at 10.2.1?