Recently I installed SketchUp 2014 Pro, but without VRay plugin. Yesterday, my friend tried to install me VRay, but for some reason it didn’t work…so, he suggested me to install older version of SketchUp. SketchUp 2013. He has that version and for him everything works fine. So, after that advice, I saved my file into previous version so that I would be able to open it after I install oldest version. After that, my other friend managed to install just VRay for my SketchUp 2014 Pro, BUT I can’t open my file that I saved in previous version. Other my files I CAN open (from the same version - 2014), but that one, from older version, can’t. That doesn’t make any sense, so please help!!! Why does this happening? Is there any way that I can covert or to resave it somehow into the SketchUp 2014 Pro??? Thank you 
Do you get an error message? Maybe you installed 2015 by mistake? Can you open the file in SU 2013?
I didn’t get any error messages, just blank screen. I deleted Vray, so everything works fine for now. Maybe I will try once again with Vray installation. Thank you so much!!! 