QGIS suddenly won't allow addition of new vector layers when running on PC (Lyon 2.12.1). I've reinstalled it, no help. I've recently changed to Windows 10 from 7, otherwise nothing much has changed on my system.
The program starts up ok, and I can open existing projects and raster files. When I try to load a new vector file however the program immediately freezes whether using the menu or layers toolbar (before I am asked to choose a layer) and I have to use task manager to close the program.
I installed an earlier (2.8) version of Qgis but this didn't fix the problem. I also did a complete uninstall (both versions), then reinstalled the newest version 2.12.3 - no improvement.
I can work with shapefiles within an existing project, but as soon as I try to add a new vector file the program freezes. Meanwhile version 2.12 works happily on both Mac and another (slower) PC.