Since I've installed Visual Fortran 2013, many .f (fixed) Fortran source files cause VS2010 (and 2012) crash on load. To isolate the problem, I tried loading just single source files (no projext or solution) with exactly the same results. VS crash on file load.
I've installed VS2012 + Visual Fortran 2013 from scratch on a second system with clean installed Win7 and the problem persists. BTW previous Visual Fortran version (2011) works fine with no crashes at'all.
.f files that crash the VS environment are NEC2 and NEC4 sources if that helps.