I have a 750 GIG hard drive almost full using ext2.

Initially my problem started because I could not mount the drive....

  727.194272] EXT2-fs (sdc5): error: ext2_check_descriptors: Block
bitmap for group 2560 not in group (block 29)!
[  727.194277] EXT2-fs (sdc5): group descriptors corrupted
[ 1316.752970] EXT2-fs (sdc5): error: ext2_check_descriptors: Block
bitmap for group 2560 not in group (block 0)!
[ 1316.752976] EXT2-fs (sdc5): group descriptors corrupted


Then I did the following command.....

fsck -b 102400000 -y /dev/sdc5

Now my hard drive when mounted is completely empty.

Just curious if I might still recover from this disaster but trying a
back up superblock.

dumpe2fs 1.42.5 (29-Jul-2012)
  Primary superblock at 0, Group descriptors at 1-44
  Backup superblock at 32768, Group descriptors at 32769-32812
  Backup superblock at 98304, Group descriptors at 98305-98348
  Backup superblock at 163840, Group descriptors at 163841-163884
  Backup superblock at 229376, Group descriptors at 229377-229420
  Backup superblock at 294912, Group descriptors at 294913-294956
  Backup superblock at 819200, Group descriptors at 819201-819244
  Backup superblock at 884736, Group descriptors at 884737-884780
  Backup superblock at 1605632, Group descriptors at 1605633-1605676
  Backup superblock at 2654208, Group descriptors at 2654209-2654252
  Backup superblock at 4096000, Group descriptors at 4096001-4096044
  Backup superblock at 7962624, Group descriptors at 7962625-7962668
  Backup superblock at 11239424, Group descriptors at 11239425-11239468
  Backup superblock at 20480000, Group descriptors at 20480001-20480044
  Backup superblock at 23887872, Group descriptors at 23887873-23887916
  Backup superblock at 71663616, Group descriptors at 71663617-71663660
  Backup superblock at 78675968, Group descriptors at 78675969-78676012
  Backup superblock at 102400000, Group descriptors at
102400001-102400044