I downloaded GroupDocs.Viewer-for-.NET-master from the github website and ran the Demo inside GroupDocs.Viewer-for-.NET-master\Demos\ASP.NET MVC\src. When previewing Dwg, execute the LoadDocumentDescription method
var d…...NET Can't preview dwg file GroupDocs.Viewer Product...NET MVC\src. When previewing dwg, execute the LoadDocumentDescript...