At last I booted win 7 by using
Testdisk. Link to solution if anyone has problem in booting windows even thought all the files are present/intact.
If you have damaged the boot sector of one of your partitions (e.g. by installing GRUB in it by mistake), you may have troubles. For example, if it is a Windows partition, you will not be able to boot into Windows any more.
Remark: if you have this problem, Boot-Repair should automatically warn and tell you the name (eg sda2) of the broken partition.
Here is how to repair it:
Via an Ubuntu disc
Step 1 - Boot on a liveCD or liveUSB
Boot your computer on a Ubuntu live-CD or live-USB, then choose "Try Ubuntu".
Step 2 - Install TestDisk in the live-session
Once in the Ubuntu live session, install TestDisk this way:
- Connect internet
- Open the Software Center, in the top bar click Edit -> Software Sources -> enable the Universe repository
Open a terminal (Ctrl+Alt+T) and type :
sudo apt-get update
sudo apt-get install -y testdisk && sudo testdisk
Step 3 - Use TestDisk
- Via the arrows and the Enter key, go to the [No log] menu,
- then select the disk where the broken partition is,
- then select [Proceed],
- then choose the type of partition (generally [Intel]),
then select the broken partition with [Boot], it will display something like :
Backup boot sector
Sectors are not identical.
A valid NTFS Boot sector must be present in order to access
any data; even if the partition is not bootable.
[ List ] [Backup BS] [Rebuild BS] [ Dump ]
Check that you have "Status ok" below "Backup boot sector"
select [Backup BS].
Via a Windows disc
This method is only able to fix the bootsector of a Windows partition.
Get a Windows recovery disk, as explained on this page
Boot on it, and use the 'fixboot' command (not the 'fixmbr' one). This should fix the bootsector of Windows.
source: Ubuntu official documentation