Yesterday I was trying to setup my old laptop as NAS server and I was trying to setup my old laptop hard-drive (which I was using as portable USB drive) for NAS storage. That old drive still contained multiple partitions including one for Windows installation. I decided to delete windows partition and use it as root partition to install Ubuntu and use rest of the drive as /home for storage. So I created a bootable USB disk of GPartEd and boot my laptop from USB.
The issue came up when I was trying to move and resize my extended partition. One of the partition had lot of data that I didn't want to loose so formatting the whole disk was not an option for me. For some reason gparted was failing on moving my extended partition and it said that can not move/resize it. I googled for some help in various linux forums and found this post in Ubuntu forums about someone had similar issue. He/She tried 'swapoff' option on 'swap' partition and it worked for him. But for me, 'swap' was already in 'swapoff' mode. So no luck there.
Then I tried something new based on that, I deleted the 'swap' partition that was in 'extended' partition, applied all the changes. Then I tried to resize and move my extended partition and it worked!!
Once again, thanks Ubuntu Forums.