ABS objects are not visible in AutoCAD® with ABS Object Enabler installed

[Autodesk]

You installed the Autodesk Building Systems 2007 Object Enabler on a computer that also had AutoCAD 2007 installed. When you opened files created in Building Systems 2007, some of the ABS objects, such as ducts and pipes were not visible. Instead, bounding boxes were visible and you received an "invalid DBX file" error message.

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