AutoCAD and Civil 3D are complex programs. Their drawings can be rather delicate at times in their complexity. Sometimes they are in need of repair. Sometimes the drawings are in such bad shape, they can no longer be opened. This applies to all AutoCAD-based programs, such as Map 3D, Plant 3D, Electrical, Architecture, Civil 3D, etc.
Here are a few commands you can use to help maintain a healthy drawing.
Purge
Purging will not in and of itself improve the health of a drawing, but it will make the drawing lighter by shedding all of its unused elements, such as blocks, layers, etc., as shown below. (The behavior of this command is rather complex and beyond the scope of this blog.)
Audit
The Audit command is available through the Application Menu, in the Drawing Utilities branch (as shown below), or it can be typed in at the command line.
The Audit command has only one option: whether or not to repair the errors it has found. The reason for this is that sometimes the drawing is in bad enough condition that the Audit repair could actually make things worse. This happens seldomly, but if in doubt, I recommend you have the Audit command simply report on the errors instead of making the repairs. You could also make a backup of the drawing (by saving it under a different name) and have the Audit command make the repairs on the backup drawing, so that you will have the original drawing still intact if the Audit command causes a crash.
There is a system variable named AUDITCTL. When it is set to 1, the Audit command will generate a text file (with an .ADT extension) listing the problems the command found and the action taken by the command to repair these problems.
Recover/Recoverall
The Recover/Recoverall commands are also available through the Application Menu, in the Drawing Utilities branch (as shown below), or they can be typed in at the command line. Recoverall is the command for Recover with Xrefs.
The Recover command cannot be performed in the current drawing; you are prompted to select a drawing instead. Then it will perform similar repairs to what the Audit command does as it opens the drawing, but it tends to be more effective since the drawing is opened afresh. It does not prompt you whether to repair the errors it finds. The Recoverall command (Recover with Xrefs) will open and check all XREFs attached (or overlaid) to the drawing as well. When complete, a report is displayed as shown below, which you can copy into the clipboard for recordkeeping, if needed.
Like the Audit command, there is a system variable that controls the behavior of the Recover/Recoverall commands, named Recoverauto.
-
If set to 0, it displays a dialog box stating the drawing is in need of repair and prompts you to proceed. If there is a script running controlling the opening of the drawing, that will be interrupted during the recovery. After the recovery, the report is listed in a dialog box.
-
If set to 1, it proceeds with the recovery upon opening the drawing without the notification – only when there are scripts running controlling the opening of the drawing.
-
If set to 2, it behaves as when set to 0, but only displays the report at the command line, not in a dialog box.
-
If set to 3, it proceeds with the recovery upon opening the drawing, without the initial dialog box notification, and displays the report at the command line. This means the scripts would not be interrupted by having to close a dialog box.
Conclusion
Autodesk drawings are complex, and throughout their development, some errors can occur in the structure of the drawing. The Purge command can help keep the drawing to an optimal size, while the Audit and Recover commands can attempt to repair errors in the drawing.
About the Author
Follow on Linkedin More Content by Jeff Morris
