We are having the same issue as the original author where I work. Sales people using DWG TrueView cannot open some .dwg files because they get an Access Violation error. When someone in engineering opens the drawings in AutoCAD and resaves it, the problem goes away. I have been unable to find something unique about the files in question.
One potential problem is that the sales staff uses TrueVIEW 2011, but all the engineers are using 2012. TrueVIEW 2012 can open every file without ever having an Access Violation, but that may also be because those using 2012 are engineers with different permissions for those files.
Before we go through with updating every sales person's version of TrueVIEW, can someone confirm or discredit the idea that the version of TrueVIEW has something to do with it? My only problem with that theory is that it is only a handful of .dwg files that cannot be opened out of the thousands that are dealt with every day.
Some further information on our problem:
Some of the .dwg files are always edited together. This is because there are 2 sheets to a drawing, so if a change is made to one sheet (e.g. XXXX-1.dwg) then the other sheet (XXXX-2.dwg) is also modified at the same time. If there is ever a problem opening one of the sheets, then the other sheet always has the same problem. This makes me think the problem is something systematic with the way they are created, edited, or saved and not just some sort of random corruption of files.