AutoCAD 2013 needs and Modify permissions to that folder. Without them, actions like saving, autosaving, or creating temporary files will fail.
This is the most common fix. Ensure AutoCAD is launching in a user-accessible folder. Make Sure You Can Write To Current Directory Autocad 2013
to function correctly and avoid permission-related stability issues. Autodesk Community, Autodesk Forums, Autodesk Forum download the required Service Pack AutoCAD 2013 needs and Modify permissions to that folder
Findings (example template to fill with actual results) actions like saving