I'm using Windows 7 and I'm having the problem of QGIS 2.18.16 crashing with any shapefile. Rasters seem to be OK. I have tried uninstalling and reinstalling 2.18.15, 2.18.14 and one older version (2.17 or earlier, I can't remember). I turned off all plugins before trying anything. I found earlier advice about changing a registry key, so I used the Windows command line to start regedit and under
HKEY_CURRENT_USER> SOFTWARE> QGISI deleted all the QGIS and then did the 2.18.16 install. I also downloaded the OSGeo4W version and tried running QGIS from that.
I haven't tried any other vector formats because I really need to work with shapefiles. I'm not having any trouble with my desktop, just my laptop. I was using the style editor when the trouble first appeared.
I looked all over at the other posts about this problem, like qgis-bin.exe stopped working and I'm not sure how to provide more information.
Edit: I tried loading a geodatabase with vectors, it worked and I changed a few symbols and saved. Upon exiting I received this same message and now I get this fail when I try opening geodatabases. I also get this fail when I'm loading the new project (with just this simple geodatabase loaded).