I had successfully dual booted my laptop with Windows and Ubuntu 16.04. After installation both the systems worked fine, but I made a mistake. The mistake was , I have updated some packages from software center but after sometime when I hadn't seen any progress in updation I shut down my laptop. After booting up again Ubuntu is not opening up, but Windows is fine. Is there any way that I can recover Ubuntu? Please help!
There is a way to boot from a Ubuntu install CD and switch over to your installation on hard disk. If you system is not really corrupted it would run. I would reinstall grub as safety measure.
If that does not work, you might have broken system essentials. First step would be to mount your partition and backup you essential data, i.e. /home/ folder. replace '' with your login name. To recover broken stuff in your installation can be quite advanced, so you should at least consider if its quicker to backup data, reinstall OS and the packages you have used. Depending on your level you could consider to install your software from the command line and put the commands is a script file and run that. That way you have a very easy time if such a thing ever happens again.
1) Start your Linux with help of the install disk
All commands need to be entered in a terminal window
- start from CD. You would need to select the BIOS boot menu, e.g. F8 or F12 or whatever your motherboard requires.
- Select "try Ubuntu"
For the next you need to know what your system partition is. If you do not know, you can find out with gparted. Type.
It will ask for your password. Then it will open a window and you see your disk and the partitions on it. Linux will use a "swap" partition which you can ignore and a system partition with the file system 'ext4'. If its more complex and you set it up, you would know the partition name anyway. If not check with the one who set up your system. Note the partition name which has the type '/dev/sda1'. I will use sda1 in the example. Modify as required.
Now we connect to partition so we can read it.
sudo mkdir /mnt/temp sudo mount /dev/sda1 /mnt/temp
Check with 'll /mnt/temp' if there is content. Now you can go with your file manager into /mnt/temp and you see the file system of your installation. You can backup data as required.
Next we shift execution to your system on hard disk
sudo mount --bind /dev /mnt/temp/dev sudo mount --bind /proc /mnt/temp/proc sudo mount --bind /sys /mnt/temp/sys sudo chroot /mnt/temp
Now your file manager only shows your file system on disk.
2) Install grub
That quite easy. The 'sda' is the name of the disk. I would recommend to put grub into the MBR of the disk (or equivalent for UEFI), because IMHO it easier to handle than the windows boot manager. If you had it in the partition your can use the partition name, i.e. 'sda1'. Note that the command needs the full path to the disks, '/dev/sda1' sudo grub-install /dev/sda
I would recommend to print out that procedure and store it with the Ubuntu install disk. You might need it again.