I had Windows 8 installed on my system, which I screwed up, and now I run Ubuntu 12.04. While installing, Ubuntu used all the 461 GB of HDD space (one partition).
Now I want to make a new partition of maybe 100 GB or so, in order to install Windows 7 alongside Ubuntu (with a dual-boot). But I can't even get a partition done. I can't change the partition in GParted either – the option is disabled.
Best Answer
You cannot resize a partition while it is in use (mounted). Hence its greyed out.
To resize your partition, you would need to boot from your Ubuntu 12.04 LiveDVD,
open Gparted, and then resize your Ubuntu partition.
Depending upon your current partition setup, you may want to shrink different partitions
If you have a large home partition (/home), you may shrink it by 100 gb, and in the free space created, create a ntfs partition which you could use for Windows.
Post your output of
so that I could better advice you in partitioning.
Edit-
As you stated that you only have single partition, just resize (shrink) it by 100 gb.