I installed Ubuntu 14.04 LTS parallel with Windows 10. After installing and rebooting, the grab window appears correctly and I have 2 option for booting from windows and one option for boot from Linux.
When I choose to boot from Linux everything's fine.
When I try to boot from windows nothing happens.
When I choose the first option "sda1" it redirects me in a black window with a flashing underscore.
When I choose the second option "sda2" it redirects me again in the grab window to select again an OS.
I tried boot-repair but no result. What should I do?