As good as Windows 7 may be, it isn’t yet perfect. Many users have encountered problems during install or when trying to partition a drive within Windows. This article will discuss methods of working around this so you can partition your hard drives without any problems.
When setting up Windows 7 for the first time, there is a dialog box that instructs you to choose a partition to install Windows 7. Sometimes this box doesn’t contain any drives, even though you may have many installed. The first move here would be to turn off your PC and disconnect all but your DVD and the hard drive you are installing Windows onto.
Occasionally the Windows setup program has trouble with RAID drives, or multiple hard drives. Unplugging extraneous hardware is something I would advocate whenever installing a new Windows operating system. It seems to speed things up considerably, and prevents issues like these.
The next opportunity Windows has to produce this error is while you are attempting to partition from within Windows 7. For some reason, known only to Microsoft, Windows files aren’t installed in nice tidy lines or clusters on a hard drive. They can appear all over the place. Even if you defrag your drive first, sometimes Windows won’t allow you to partition a drive because there are system files in the way.
To circumvent this problem I suggest using a third party program GParted. I use GParted as it's Linux based (GNOME) and very reliable. Simply download the file which is an ISO image, burn it using your favorite burning tool, and choose the “burn ISO image” option. Once completed, restart your PC with the disk in the drive and boot from it.

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