HOW TO
In ArcObjects, creating an add-in with Microsoft Visual Studio requires running the ValidateAddInXMLTask. This task requires Visual Studio Shell 12.0 to run with the necessary packages installed and without interruption, otherwise errors may be returned.
The Microsoft Visual Studio Shell 12.0 library is a part of Visual Studio 2013 Shell (an older version of the software). Therefore, the download link is not located on the main Visual Studio Downloads page, and is separated as isolated shells. The following steps describe how to locate and download the Visual Studio 2013 Shell.
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