I tried to upgrade from Ubuntu 13.10 to 14.04LTS. In between it asked about some configuration files whether to keep or replace them, for all I chose to replace them on each prompt but at the end installation said the machine is corrupted and cannot start.
NOTE: For kismet module while upgrading modules it gave an error popup.
I get the black screen with blinking cursor and also the below error screen.
ubuntu ext4-fs error (device dm-0): hdtree_dirblock_to_tree:920
When I hold SHIFT key while boot then I can choose an older kernel version and then I can login inside, I see the version show in About Ubuntu as 14.04LTS.
Please help on how can I fix the issue as my machine by default does not start and I get the black screen with blinking cursor.