Cannot open certain drawings with eDrawings 2014 SP1.0

I've noticed on our system that we cannot open certain Solidworks drawings wiht eDrawings.  We have EPDM 2014 SP1.0 installed, all CAD machines are running Solidworks 2014 SP1.0 and everyone is using eDrawings 2014 SP1.0.  The only thing is that not all of our CAD files are in the latest (2014) file format, some are in 2012 and 2013 formats (because we have not found a need to open and resave/change them yet).

Anyway, within the PDM, randomly, certain files (in particular drawings) will not open.  You can double click on them, and eDrawings shows up, but then displays nothing.  No errors or whatever.  But then another user can view it on their machine without an issue.  But this seems limited to a few machines only, one of which has Solidworks CAD on it, the other just has a read-only EPDM Viewer license.

There is no error message; it's just nothing shows up when eDrawings opens.  And eDrawings isn't stuck or anything...it just doesn't display anything.  But this is sort of a hit or miss kind of deal, and the people who are having the problem have read access (at least, if not write/check-out access) to the files (except for the Viewers, which can only read the files).  But still, they should be able to view them at least in the viewer.

Ideas?

SolidworksSolidworks Pdm enterprise Pdm