Reboot error after reformatting a partition
I resized my 1.5TB (with Windows-7 installed) to make space for "Linux OS" and personal data. I did it using live-USB version of the Gparted, and it worked well. I installed linux and formatted the data space as a different partition during the linux install process. I used Ext3 for this partition. All worked well until here.
Now, I used Gparted on my linux machine to change the formatting of the data-space partition from Ext3 to NTFS. Here, please note that all the partitions are on the same physical hard-drive. That is, when I changed the partition formatting from Ext3 to NTFS, the Linux was running on the same physical hard-drive; but, of course, in a different partition. The formatting worked well, with no error.
Now, when I reboot the linux, it can't boot. It shows some error like difficulty in mounting the linux partition (which, I didn't touch). It asks for a root password to fix the issue, or CONTROL+D key to reboot.
When I choose to fix the issue, what commands should I use?
Or, is there any other way to fix this issue ?