I have been using Mathematica 10.0.2 in my laptop with Windows 8 and it was working fine. One day I would try to open it as usual but it would not launch (I'd click at its icon in the start menu and absolutely nothing would happen, not even the kernel would start). However, in the task manager, Mathematica would appear in the list of "background processes". I can open the Mathematica 10.0 kernel, though.
I tried to reinstall it, but the same problem remains. I also tried version 10.3 without success. However, Mathematica 8.0 works fine (I would need a recent version though).
Could anyone help me solve this problem? Many thanks.