Hello,New to the forum. This is my first post.We recently upgraded from various versions of Land Desktop (2006-2010), to 2014 Infrastructure Premium. Most of the files on our server are 2006. Any time I attempt to open, insert, or recover an older drawing using Raster Design, Map, or Civil 3D, I get said fatal error.  I can open them with vanilla autocad, but they won't open with any of the civil stuff, even after I save them to the current version. I've only been using the 2014 line for a few days, and I'll surely figure this out, but thought someone here might have run across this already. I am running Windows 7 Pro 64 on a Xeon E5 processor, 16GB Ram, 1TB hard drive.Regards,Tom

Try this:
http://knowledge.autodesk.com/support/infrastructure-design-suite/downloads/caas/downloads/content/revit-structure-2014-update-release-2.html

Turns out the error was isolated. I have been working in 4 projects, all containing 20+ drawing files, and every one of them gave me this error. I assumed that would be the case for all 2006 files, but this morning I opened a drawing file from a different project and had no errors. Writeblocking out the entire drawing for each file in the affected projects fixes them. Not sure what element is in these files that is causes the error, but whatever it is gets left behind in every file it touches. I tried purging everything, even went so far as to delete all elements from one of the files, but it would still give me the error. Writeblocking is the only thing that I've found that works.