Hi,
I successfully converted many 9.3 .NET projects to 10.2 Add-Ins a few months ago using VS2012, .NET 3.5 and an ArcMap 10.2 30-day trial version for debugging. All was fine then and everything converted with no problems.
We now have our licenced 10.2 installed, but I can no longer debug the same projects I was using before. I can get ArcMap to launch when I go to debug, but I do not see the Add-In anywhere in the ArcMap application. It is not listed in the 'Customize' window or anywhere to be seen.
Any ideas as to what is going on??