Although I'm not sure how to go about getting an older version of that file that works will all three versions of Civil 3D that we have installed so I can test that through with a (partial) fix! *high five* The use who I had test it on his computer (using AutoCAD MEP) doesn't have the AeccNetwork.dbx file so maybe, just maybe, that will fix it.

Users just started complaining about it last week. I guess this will be my next course of action although I don't believe there have been any updates/SP's installed within the last two weeks or so because I'm sure I would've heard of this happening sooner. I've got Civil 3D 2013/2015/2015 installed and they each have a different version date (and not the one mentioned in the post). I've read a few posts about the AeccNetwork.dbx file and the version date.

We recently had a new piece of software installed but I had the IT department uninstall it to rule it out. Our IT department has things locked down pretty tight so there's very little I can do on my own. I don't know what's available for restore points (if any) on my laptop.

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