"Unable to create .esriAddIn: missing ESRI ArcGIS Add-In SDK component(s)"

[StanShelton]

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?

[StanShelton]

I have the ArcObjects SDK installed and can create new Add-Ins in VS 2012. My .NET framework is set to 3.5.

If I'm reading the link Backward compatibility of 10.2 ArcMap AddIns with ArcMap 10.1 correctly, I have to recreate my Add-Ins. I was hoping to avoid that.

Thanks Sol

[StanShelton · Accepted solution]

I got an answer from ESRI Technical Support (thanks Srishty).
She said that the problem is a defect (#01599069). She also gave me the following workaround:

1. First we change the build version from 10.0 and 10.2 in the config file.
2. Then we right click the solution file and select "Unload Project" (third from the bottom).
3. Then we click on "Edit<solution file>" (Second option)
4. This opens the csproj/vbproj  file, then we go at the very bottom of the csproj/vbproj file and replace "ESRI.ArcGIS.AddIns.targets" with "ESRI.ArcGIS.AddIns.11.targets".
5. After we replace "SAVE" then Reload the Project.
6. Project would probably need to get restart to reflect the changes made so close and reopen the solution file and build it again.