I was sent a group of dwg files that seem to have been made with Civil 3D. The problem is that almost half of them display the "Drawing file is not valid" message when I try to open them with AutoCAD 2011LT and 2012 Full. The same happens when I try to open them with TrueView 2013. If I try to convert them, TrueView says it there was some data problem opening them.
When opening them in Notepad I see that it says AC1021, so it's saved as a 2007-2009 version. I got no .BAK files, I can't recover the .DWG's and I can't contact those who originally made the files.
I have attached one of the corrupt files for reference.
Any ideas what else I could do?
We have been having a lot of problems with this lately. What I did to fix the issue was open a blank drawing -> etransmit -> select the corrupt file and package. Then unzip the file and it opens.
We have noticed that if an email with a .dwg attachment is forwarded with an iPhone, it somehow corrupts the drawing and you get the Drawing file is not valid. error when tring to open the file. The same email sent through Outlook arrives intact.
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