Oct 18, 2013 - Autodesk released a Hotfix for AutoCAD Civil 3D 2014 for the new Windows 8.1
This hotfix for AutoCAD based 64-bit vertical product fixes Model Documentation and IMPORT command related issues on 64-bit Windows 8.1. Consult the readme file for installation instructions.
The Model Documentation Hotfix ONLY applies if you are running Windows 8.1.