This viewer is compatible with both 32-bit and 64-bit operating systems (Windows® XP®, Windows® Vista®, and Windows® 7. 

Note: This viewer is compatible with Trimble® QuickPen PipeDesigner 3D®, Release 2012 v2, and can be used only on computers running AutoCAD® 2012, AutoCAD® Architecture 2012 and AutoCAD® MEP 2012. It will not work with previous versions of Autodesk applications or Trimble® QuickPen PipeDesigner 3D®. Please make sure you download the viewer for a compatible version of AutoCAD.