Boot from the Ubuntu Live CD and open Terminal.
Run this command: sudo fdisk -l
(to get the device name):
radu@Radu: ~ > sudo fdisk -l
[sudo] password for radu:
Disk /dev/sda: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders, total 488397168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x004aa9ec
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 718847 358400 7 HPFS/NTFS/exFAT
/dev/sda2 718848 61431807 30356480 7 HPFS/NTFS/exFAT
/dev/sda3 61432621 463410989 200989184+ f W95 Ext'd (LBA)
/dev/sda4 463410990 488392064 12490537+ 83 Linux
/dev/sda5 61432623 450826239 194696808+ 7 HPFS/NTFS/exFAT
/dev/sda6 450828288 463409151 6290432 82 Linux swap / Solaris
In my case, my Ubuntu is on: /dev/sda4
.
Run sudo fsck /dev/sda4
(you should change /dev/sda4
with your device where is installed Ubuntu). Restart the system and boot normally.
Sources: How to Fix an Ubuntu Error: "No init found. Try passing init= bootarg".
Another related answers you can find here: How can I repair grub? (How to get Ubuntu back after installing Windows?).