Note: Drawings that are stored in BIM 360 may be opened as read-only if they contain circular references. If you see this error message when opening a drawing, resolve any circular or duplicated references in the drawing when possible and save the drawing. When opening certain drawings from BIM 360 using Desktop Connector, the following error message may be displayed: "The process cannot access the file because it is used by another process." This error may occur if a drawing contains circular or duplicated references, and may result in broken links to the referenced drawings. This hot fix also contains the Autodesk Civil 3D 2021.0.1 Hot Fix which addresses an issue that caused Civil 3D 2021 to close unexpectedly when opening a drawing with a pressure network pipe run that contained curves. For more information, see the Desktop Connector Release Notes. To resolve this issue, install the Autodesk Civil 3D 2021.0.2 Hot Fix and Autodesk Desktop Connector version 13.
The Autodesk Civil 3D 2021.0.2 Hot Fix addresses a stability issue that occured when opening a drawing that contained either unloaded or circular xrefs. Release Notes for Autodesk® Civil 3D® 2021.0.2 Hot Fix