Which of the hundreds of different Linux distributions might you have on your computer?
Exactly how did you try to make an independent partition of 10GB on your linux? Were you doing it from Linux? windows? some other Live CD?
Do you have a Linux Live CD? If you do, boot it up and run this command: fdisk -l (Lower case Letter L in the command), you need to be logged in to the terminal as root for the command to work. Post the output here.

Linux - Release 4.1(savir)
kernel - linux 2.6.XX

I has 300GB hard disk, and 2GB RAM, to develop a linux system, I need a 10GB partition.

answers to your queries...

1. I tried with gparted, but this made me to loss data
2. I tried at linux
3. I tried with fdisk -l too, but I am not able to create a new partition

My system condition is I can access D:/ only when I mount it in linux... My question is whether it is possible to generate a partition in a disk which needs to be mounted...?

-Audhil...

fdisk -l lists the partitions that exist on your system.
Can you post output?
How did you install linux?

http://bosslinux.in/boss-4.0

that is a new one for me , first time i heard of it

without knowing exactly what you did in Gparted and without knowing the exact partition layout


and without knowing what research on partitioning you have done
There is not much i can do

some basics
there can ONLY be 4 primary partitions
and MS windows 7 wants 2 of them
a linux distro needs a few partitions

/boot ( if you do not replace msWindows7 bootloader )
needs to be a primary
the rest can be logical partitions on the 4'th primary

with win7 MS made some changes to the NTFS file system
it is BEST to use the win7 tools ( built in to win7 )to shrink a windows partition FIRST
then use gparted to reformat it


it is likely that the data on your "D:\\??? partition is gone ( for good )
but maybe not
IF you STOPPED using that computer at the first sign of trouble

and on a DIFFERENT computer downloaded "SystemRescueCD"
burn it to a cd
there are some recovery tools on it

but if you did not stop using that computer it is likely that the data is gone


I take it you did heed all the warnings all over the web and on every guide
BEFORE using ANY partition tool or changing a partition do these 3 steps
1) back up your data
2) see step 1
3) see step 2

what guide were you fallowing on repartitioning a drive
and making room for a second operating system

the gparted documentation
http://gparted.sourceforge.net/displ...me=help-manual



and this guide is for linux mint 12 - a little old
but will point you in the right direction
http://www.howtoforge.com/dualbootin...-linux-mint-12