I have lenovo G510 laptop. Initially it was running on Win 8.1, I wanted to install Ubuntu 12.04 LTS alongside it. after installation I couldn't boot my Win8.1 (I choose it, after one second it return me to the select screen again!).
I have tried solution here but with no response. Then I see a comment about load UEFI default settings. then I reload it to be
Support Legacy - Boot Legacy First
At this point every thing hanged !
The select screen has gone, trying to install win 8.1 on another drive (Primary) fails (it start the setup and after the first reboot at the setup it doesn't boot win 8.1 and hang - although booting from the DVD is still working)
Any solution that can help without affecting my data nor the previous win 8.1 drive.
Drive Information: MBR
Partition 1: 350MB - System reserved Partition 2: 80GB - 50GB free - primary (original win 8.1) Partition 3: 365GB - 242GB free - primary (data) Partition 4: 20GB - primary (the second win8.1 installation)