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" Note: Fabrication CADmep 2015 will only run within AutoCAD 2015 or one of the AutoCAD 2015 vertical products such as AutoCAD MEP 2015, AutoCAD Plant 2015, etc. "

https://knowledge.autodesk.com/support/autocad/troubleshooting/caas/sfdcarticles/sfdcarticles/How-to...