[devils casper]

There shouldn't be any problem in formatting that unallocated space in NTFS. There isn't anything wrong in partition structure of your HD.

Try to format it using Ubuntu LiveCD as suggested by Jonathan183. In case, it doesn't work, format it in ext3 filesystem and post the output of sudo fdisk -l command here.

[Artesia]

Aaah, of course. Here's the fdisk info:

Disk /dev/sda: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xf9535e7e

Device Boot Start End Blocks Id System
/dev/sda1 * 1 19130 153661693+ 83 Linux
/dev/sda2 19131 19457 2626627+ 5 Extended
/dev/sda5 19131 19457 2626596 82 Linux swap / Solaris

Disk /dev/sdb: 750.1 GB, 750156374016 bytes
255 heads, 63 sectors/track, 91201 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x000098ec

Device Boot Start End Blocks Id System
/dev/sdb1 1 52268 419842678+ c W95 FAT32 (LBA)
/dev/sdb2 52269 85050 263321415 83 Linux



I'll try the live CD idea and report back, right after I get some sleep.

[devils casper]

Good Luck and Good night !

Do let us know how it goes.

[Artesia]

The live CD trick worked! Partition successfully created. Two other formats were available via live CD in addition to ntfs. These were jfs and xfs. This is odd but I'm glad it's solved.

I really appreciate your help.