Primary partition, namely,
primary drive; it is a kind of partition just like extended partition and logical
partition. Primary partition is the key which storages necessary files and data that
needed to boot operating system. We can't run operating system without it. Therefore,
there is at least one primary drive in hard disk and a maximum of four. Each drive has
special characteristic, windows built-in disk manager may be unable to handle them, so
other software would be essential for managing them more smoothly.
Here, I want to show you a kind of resize partition software to
resize primary partition, as also extend,shrink, move operation and etc. It
called Partition Assistant with several editions to support
primary drive on each kind of systems. After download and run it, you will see:
(Attention: if don't want to reboot computer, select Extend Partition, as when use
the second, if your drive is working now, the program will prompt reboot computer.)

If choose the above Extend Partition, read the clue carefully in
view.

Next, after click two times "Next", extend C: drive, just drag the direction
that arrow shows, never need to move D:, C: drive will get more space from the
unallocated space automatically.

For more convenient functions, choose the Partition
Management.
From the follow view, it shows you which partition is
"primary" and how many primary partitions. Image that: you have a C: and D: drive and
some unallocated space.

Then, look at the procedures step by step:
1. Extend C: drive:
click it, at this time, you need move D: to put unallocated space behind it to make room
for extending C:, read the Icons in the view:

2. Resize primary partition to smaller: Drag the slider to the left, easy to
do.

Attention: Each step you should click "Apply" in the tool bar to take
effect.
Besides resize
partition functions, you could extend
a partition, create and format partition, wipe hard drive, etc.
It's easy to resize primary partition with Partition Assistant.
You can choose Partition Assistant's different version as follows according
to your OS version, Windows 8, Windows 7, XP, 2000, Vista or Server 2003, 2008.
Buy Partition Assistant
Download
Partition Assistant