Compatibility 101 – part 1

Part 1 of 2.  As a support specialist, I get this question a lot; “I’m trying out Civil 3D 2011 while doing projects in 2010 and now the drawings can’t be edited in 2010”.  This may be obvious to many of you now, but there are still many out there who don’t know.  This article is for them.  Read on for more…

When contemplating Civil 3D and how compatible (or not) it is with other versions, you are confronted with several possible scenarios.  Any particular scenario may have multiple options, but generally, each has a best practise.

Let me say that the first line in the compatibility discussion is this:
A Civil 3D file is not backwards compatible in any Civil way – AT ALL.
The moment a file is saved in any version of Civil 3D (at least so far), it will NEVER be editable in any previous version of Civil 3D, period.

Let me qualify that statement a little.  As an AutoCAD user, you probably know that historically, every third release of AutoCAD is a new DWG version.  2004, 5, and 6 are interchangeable, 2007, 8, and 9 are interchangeable, 2010, 11, and presumably the next release will be as well.  This is plain AutoCAD however.  I CAN open a file saved in Civil 3D 2011 using Civil 3D 2010 because they are the same DWG version.  It’s the Civil 3D objects contained within the file that cause the incompatibility.

Feel free to edit the AutoCAD stuff in that file all you want.  Make some text, draw some lines, etc, but if you want to edit the alignment or make a new one, you need to open that file in Civil 3D 2011 or later.

If you MUST edit that file in Civil 3D, know that you can’t, ever.  There is a workflow to kind of get around this problem…

  • From Civil 3D 2011 you can export the Civil objects out to an XML file.
  • Export to AutoCAD that file out to a new DWG.  Remember, this tool EXPLODES all of your Civil objects into their basic AutoCAD primitive objects like lines, text, arcs etc.  This file is devoid of any Civil 3D objects.
  • Start Civil 3D 2010 and begin a new file using your 2010 DWT file.
  • Insert the Exported DWG as a block and explode it.
  • Import that XML file from the first step.

This workflow gets some of the Civil objects into Civil 3D 2010 and gets the AutoCAD stuff there as well.  Sounds pretty good?  Well, know this, none of your old labels are dynamic, as they are now text.  Your profile view is not a profile view, it is lines, text, polylines etc.your sections are…well, you get the idea.  You can certainly create new objects, but the ones you created using 2011 are gone.  This is not a perfect solution, but it’s a solution.

A snag in this solution is that not all of your Civil 3d objects can be written out to and in from XML.  Corridors currently are not compatible with XML.

Another snag in this “solution” is…what if you don’t have a Civil 3D 2010 DWT file?  You need to have styles right?  There is no way that I know of to get 2011 styles into a 2010 file.  If you started your Civil 3D career using 2009, you probably have a 2010 file to go back to.   If 2011 is the first Civil 3D you’ve used, well, it would appear you have a problem.

That’s the state of affairs as of February 1, 2011.  Maybe one day we’ll have a solution that is a little better than this one.

Stay tuned for part 2 where I discuss other possible scenarios.


  1. Neil Jones says:

    Conspiracy theorists may suggest that this is a ploy by Autodesk to get all users either on subscription or to upgrade to every new release….I couldn’t possibly comment….!!!!

    • Matt Kolberg says:

      I won’t comment on the conspiracy, but I will give my opinion on a possible “why”.

      There are new objects that get created every year; some you can see, like intersections, some you can’t, like a new style type. Non-display, but an object nonetheless.

      When openeing a 2011 file in 2010, how would we expect the 2010 file to handle that object when it doesn’t exist in the 2010 software?

      I’m not saying it can’t be done, but it’s certainly one reason why we have compatibility issues. I was once told by they who will remain namesless that it would take almost as much development time to make Civil 3d backwards compatible as it does to code the entire program.

      It’s already fairly expensive. Do we want to make it more so?

      Anyway, you can take that at face value. I don’t know the numbers and I can’t prove anything so read into it what you will.

      • Nick M. says:

        If Autodesk would spend the time and money, to resolve the Civil 3D backward compatiblity issues, they could easily make up that expense, on new upgrade sales. I know of alot of companies that have not upgrading cause of the know backward compatibilty issues. Some companies have switched to the competition due to their software being more backward compatible than Autodesk.

  2. R.K. McSwain says:

    Good information. Thanks.

  3. Michaela says:

    A good reminder. Thanks. As a side note, InMotion’s IMSolutions has a tool that lets you export and import Civil 3D styles and settings. We’ve used this tool to take styles from a 2011 drawing into a 2010 drawing. It works perfectly every time and well worth the money.