ERROR
Building an ArcGIS Explorer Add-In project in Visual Studio 2008 results in the following error message in the Build Errors window in Visual Studio:
"The ArcGIS Explorer SDK is not correctly installed - 'ESRI.ArcGISExplorer.targets' not found - (ArcGIS_E3SDK='')".
The Visual Studio process does not correctly read the new environment variable set in the ArcGIS Explorer SDK installation.
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