So here's the story:
I have a Vaio Fit 15E (full spec: SVF15218gb) which has restricted boot enabled by default!
I mounted the iso file of Ubuntu 13.10 on a flash drive and tried restarting the system but nothing happened and windows 8 started as usual!
Then I went through BIOS settings and turned off the UEFI and switched it to Legacy!
Finally I could manage to install 13.10 "Alongside Windows 8" and restarted the system and removed the flash drive, but nothing came up! neither Ubuntu nor Windows 8! Instead an error showed up:"Operating system not found!"
What I did was turning off the system and enabled the UEFI back. System started normally and booted windows 8 as usual, as nothing else is on the machine!
I remember installing Ubuntu alongside Windows 8 on a pc before which it showed me a screen with the options of Windows 8 or Ubuntu (grub? gurb? or something?)! But now on my Vaio, it's a little complicated I think!
Any ideas how I can dual boot Windows 8 and Ubuntu?