Hello I found the reason. I have to let boot loader installed in the first partition where my previous ubuntu keeps boot loader rather than have boot loader installed on a new partition.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/786096 Title: Installer crashed -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs