How to extend system partition in Windows 7/Vista/XP, Server 2003/2000 and Server 2008?

Quick Links:
1. Why do we need to extend system partition?
2. Expand system partition by using Partition Assistant utility. (NEW)
3. Extend Partition by using Windows disk management.
    - Launch windows disk management to extend C: drive.
    - Extend Volume greyed out in disk management, what can we do?
    - Generate a contiguous unallocated disk space to extend system partition.
    - Extending system boot partition.
    - Extending partition volume by using the command line.
    - Expanding system partition from my experience.

Why do we need to extend system partition?

As applications continue to be installed into the Windows system, one day, suddenly you will find that the system partition do not have enough free disk space, and when every time the system starts, Windows always prompts the following information:

You are running out of disk space on SYSTEM (C:), To free space on this drive by deleting old or unnecessary files, click here…

In this case, we have to delete the unwanted file to get more free space in order to ensure the normal operation of Windows. However, deleting files is not the best way, because my system disk have a total of 250GB, the system boot partition (C:) is only 20GB, and 230GB was divided to data partition (D:), it is clear that (D:) space is large enough, and now the best approach is that distribute 60GB from the (D:) to (C:) to extend system partition, so that you can permanently solve the problem by using the Extend Partition Wizard of the "Partition Assistant". Here is the layout of my system disk before extend system volume as shown below:

Expand system partition by using extend partition wizard of Partition Assistant.

Extend Partition Wizard is specially designed for extending your system boot partition and other partitions on a disk. It can fully utilize the free space and unallocated space on the disk to meet your needs. The program will automatically shrink large partitions and moves them to release more space to increase the size for the your appointed partition. It's easy and safe without loss of data, without reformatting partition. Besides, the Partition Manager can help you to realize more advanced partition operations.

Step 1:

Start the Extend Partition Wizard of Partition Assistant as administrator privilege, and select the partition that you wish to extend (eg. "Extend system partition") shown below:

Step 2:

Click the Next button, skip a welcome screen, and select partitions which will need to be shrunk to take the free space from them. The screenshot is as follows.

Select partitions that need to be shrunk

Step 3:

Specify a new size of the partition that you are extending by moving slider or by entering proper value into Partition New Size box, and you could preview the changes in time.

Step 4:

Review your harddisk structure before and after the change, and confirm these operations that will be processed. Then click the Proceed button and click Yes to start.

Step 5:

Show the operation is being processed. You will receive a report when completing. Then view C: drive in Explorer, you found it has been extended.

Resize Partition with Partition Assistant: As a partition manager, Partition Assistant is more flexible for you to choose which partition for resizing, just operate these functions such as extend, shrink, move, delete partition etc in one interface. Click right in the partition, you will see the functions: Resize, Move, Delete, Label, Format, in the "Advanced" menu option, you can Change letter, Hide/Unhide Partition, Set Active Partition, Convert File System, Check errors, Wipe data. It showed below:.

For more information: Extend Partition Assistant Professional Edition
Click here to download the Partition Manager to try.
Buy now Partition Assistant Professional Edition to extend your partition

Extend Partition by using Windows disk management.

To expand/extend system boot partition and increase its free space in Windows 2000, Windows XP and Windows 2003 is very difficult to do in the past time, because their built-in Disk Management did not provide the functions of extending partition or shrinking partition, this would have to use third-party tools such as Partition Magic, Disk Director, and other partition management software to accomplish the extending volume operation.

However, in Windows Vista, Windows Server 2008 and Windows 7 times, Expanding Volume is no longer a difficult task, because Disk Management of Vista, Win2008 and Win7 have been built in the functions such as expanding volume and shrinking volume, and also include extending system partition, which is very easy to use without relying on 3rd party partition utilities. It's able to extend primary partition and logical partition, at the same time, this feature can not only resize (adjust) the size of a basic partition on a basic disk, but it can also resize dynamic system volume on a dynamic disk. Yet partition magic and other disk management tools can not handle dynamic disks. Thus, resizing a dynamic disk volume is indeed a good feature on Vista, Windows 7 and Windows Server 2008. Now come to experience!

1. Launch windows disk management to extend C: drive

Click Start Menu -> Control Panel -> System and Maintenance -> Administrative Tools -> Double Click Computer Management -> Storage -> Disk Management. Or directly type "diskmgmt.msc" to Start Menu -> Run. It showed below.

2. Extend Volume greyed out in disk management, what can we do?

Then right-click the system boot volume (C:) you want to expand, but you will find "Extend Volume ..." is a grayed out and unusable state, how is this going on, can not be extended? The screenshot is as follows:

In fact, it is not impossible to extend system partition (C:), but to activate "Extend Volume" option have an rule. Rule is: Disk Management tool is only able to extend the volume with focus into "next contiguous unallocated space", in other words, there must be unallocated disk space after the partition that you want to extend. As there is no "contiguous unallocated space" after the (C:) partition drive, so "Extend Volume" option is grayed out.

3. Generate a contiguous unallocated disk space to extend system partition

How to generate a next contiguous unallocated space here? The method is to reduce D: drive (shrink volume D :) at first, then in the extra unallocated space to create a new partition. Here copy all data of D: drive to the newly created partition and delete D: drive, so that the system partition can be enlarged to the "contiguous unallocated space", follow these steps:

Shrink volume DATA (D:) from 230GB to 120GB as follows:
After clicking "Shrink Volume…" option, the following screenshot is opened:
Click the Shrink button to confirm, then the disk will generate an unallocated space of 110GB as follows:
Now you can create a new partition in the unallocated of 110GB, then copy the files of (D:) to the (E:) partition, the following is newly partition (E:)

And then, delete (D:) to release 120GB of unallocated space to extend system boot partition (C:).

Please try to Extend Partition Professional Edition of Partition Assistant to directly extend your system partition if a congiguous unallocated space can not be generated.

4. Extending system boot partition

After deleting (D:) partition, it is recommended to change drive letter from E: to D:, thus maintaining the drive letter is the same as before. Now you can extend system partition from 20GB to140GB. In this following screenshot, Windows Disk Management is certainly able to extend or resize system partition by using the contiguous unallocated disk space:

After you click "Extend Volume" option, will open an Extend Volume Wizard to help your operation, the following screenshot is the new condition after expanding system partition:

Now you see the above, the system boot partition (C: drive) has expanded from 20GB to 140GB.

5. Extending partition volume by using the command line

Extending a partition or volume can be done via DiskPart.exe, or command line interface. This works can be done in both Vista, Windows Server 2008 and Windows 7. Start with the following steps:

Click Start and type CMD, then press Enter.
In the command prompt type
DISKPART.exe
Select the right hard disk and partition to work on. Typically this should be disk 0 and partition 1.
SELECT disk 0

SELECT partition 1

Note: You may want to execute a "LIST" command to view your existing disks and partitions before attempting to expand volume. Needless to say, if you don't have any space you can use on the same disk, you will not be able to extend the partition any further. So no real harm can be done here.
LIST disk

LIST partition
When the right disk and partition were selected, execute the "EXTEND" command. If you don't specify the size to extend by, then the command will extend the partition by using all of the contiguous space available on that disk.
EXTEND
The above command will enlarge the partition by using all of the contiguous space available on that disk.

EXTEND size=2048
The above command will enlarge the partition by 2048MB (increase 2GB free space to the partition that you were selected).

6. Expanding system partition from my experience

1). There must be contiguous unallocated disk space after the partition that you want to extend. If haven't a contiguous unallocated space you can directly use Extend Partition Professional Edition of Partition Assistant to realize the expansion.

2). For extending dynamic system volume on a dynamic disc, its method of operation is exactly the same as the above extending basic disk.

3). When no contiguous unallocated space, there are two ways of creating a contiguous space to extend system boot partition.

A. The easier way: Copy all data and files in D: drive to an USB hard disk (or other external disks), right-click D: drive and click "Delete Volume…" to generate a contiguous unallocated space.
B. Troublesome way: Shrink the D: drive partition to create new partition (e.g. E: drive), move D: drive data and files to E: drive, and apply "Delete Volume…" in D: drive.

4). Windows Disk Management can not move partitions from one location to another location, which is one of its disadvantages.

5). Windows 2000/XP/2003 Disk Management does not support for extending partition and shrinking partition, only the Vista/2008 and Win7 are able to extend volume and shrink volume in the basic disk and the dynamic disk.

6). On dynamic disk of Windows 2000/XP/2003/2008/Vista and Windows 7, it is possible to extend volume to another disk space by using "Spanned Volume" function, but this feature does not support for extending system partition.

7). Common partition software such as Partition Magic, Disk Director, Partition Manager, Partition Master and Partition Wizard support basic disks and does not support dynamic disks.