How to Extend System Partition, Expand and Enlarge C: Drive Partition for Windows 8/7/XP/Vista/2000 and Windows Server 2000/2003/2008/2016/2019?

Mar 08, 2018

How to extend system boot partition on basic disks with Windows partition manager for Windows 8/7/XP/2000/Vista, and Windows Server 2000/2003/2008/2016/2019? This article will guide you the most easily, efficiently and directly way to resize partition.

Extend System Boot Partition in Windows 8.1/8/7/Vista/XP and Windows Server 2012/2003/2008

As applications continue to be installed into the Windows system, one day, suddenly you will find that the system and/or boot 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…

Low Disk Space

In this case we have to delete the unwanted files for getting more free space and ensuring Windows normal operations, however, deleting files is not the best way. If my system disk has a total of 250GB - the system boot partition (C: drive) is only 20GB and 230GB was allocated to data partition D: and E:. It is clear that D: partition space is large enough, and now the best solution is to allocate 60GB (even more) from the D: to C: by extending system partition. You can permanently solve the problem by using the Extend Partition Wizard of AOMEI Partition Assistant which is considered as a helpful Windows partition manager. Here is the partition layout of my system disk before extending system volume as shown below:

Disk Management
  • Solution 1
  • Solution 2
  • Solution 3

AOMEI Partition Assistant Pro Edition is specially designed for extending system boot partition and other partitions on a disk for Windows 8.1/8/7/XP/Vista 32 & 64 bit. It can fully utilize the free/unallocated space on the disk to meet your needs. The program will automatically shrink large partitions to release more space and then increase the size for your appointed partition. It's easy and safe without losing data, without reformatting partition. Besides, this Windows partition manager also could assist you to realize more advanced partition operations.

Step 1: Download AOMEI Partition Assistant and run it as administrator privilege, you will see the following Main Window, click the "Wizard" option on menu bar and select "Extend Partition Wizard". (Or directly click the option in the red region)

Extend Partition Wizard

Step 2: Get the following "Extend Partition Wizard" dialog. Please select the partition that you wish to extend (eg. "Extend system partition") shown below:

Extend System Partition

Step 3: Click "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

Step 4: Specify a new size of the C: 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.

Partition New Size
Drag Slider Bar

Step 5: Preview and confirm these operations by clicking "Proceed" and then choose "Yes" to start.

Hard Disk Layout

Step 6: 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.

Extend Partition is being processed

Then, extending system partition is complete successfully!

As a top Windows partition manager, AOMEI Partition Assistant is more flexible for you to choose which partition for resizing, just operate these functions such as extend, shrink, move, split, merge, copy partitions, etc in griphic interface. Right click the target partition, you will see the functions listed: Resize, Move, Split, Merge, Allocate Free Space, Copy, and in the "Advanced" menu option, you can Change Drive Letter, Hide/Unhide Partition, Set Active Partition, Covert Partition Type, Convert File System, Check Partition, Wipe data. Please see below:

Partition Manager

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Case Study - Resize Partition: When you need to increase system partition size and there is a partition next to it, please do as the following steps: (Note: Suppose you need to extend drive C: and drive D: is next to C: drive)

1. Launch AOMEI Partition Assistant and the following main window will be presented in front of you.

AOMEI Partition Assistant

2. Select D: partition to be shrunk. Right-click on D: partition and choose the "Resize Partition" in the drop-down menu.

Resize Partition

3. You can shrink the D: partition in a pop-up dialog box. Position the mouse pointer on the left handle. Drag the slider bar rightwards in order to shrink D: partition size when the mouse pointer changes to a double-headed arrow.

Shrink Partition
Partition Shrink

4. Click "OK" to return to AOMEI Partition Assistant Main Window. Then there is an unallocated space on the right side of C: drive partition. Then, select the system C: partition and position the mouse pointer on the right handle of C: partition. Drag the slider bar rightwards to increase the size of system C: dirve when the pointer changes to a double-headed arrow.

Extend System Partition

5. This two operations will be added to "Pending Operations", you need to click the "Apply" on toolbar to execute the tasks. (Please refer to the following screenshot marked in the red region.)

Click Apply

6. After clicking "Apply", the following dialog box will pop up. You can click "Proceed" button to confirm these operations. (Note: If some applications are running on the D: partition, when click "Proceed", AOMEI Partition Assistant will prompt you that the computer needs to be restarted to realize these operations.)

Click Proceed button

7. After clicking "Procced", all operations will be processed immediately. Please wait patiently and you will receive a message when all tasks are completed.

Execute the Resizing Partition Operations

Free Download Windows Partition Manager to Try.

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To expand/extend system boot partition and increase its free space in Windows 2000, Windows XP and Windows 2003 is very difficult 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.

However, in Windows Vista, Windows Server 2008, Windows 7 and Windows 8 times, Expanding Volume is no longer a difficult task, because their Disk Management have been built in the functions such as expanding volume and shrinking volume, and also include extending system partition, which is easy to use without relying on 3rd party partition utilities. It's able to extend primary partition and logical partition.

1. Launch Windows built-in 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.

2. Shrink Volume to generate unallocated space

  • Select (D:) volume and right click on it, and then, choose "Shrink Volume..." as shown below:
    Shrink Volume

  • After clicking "Shrink Volume…" option, the following window will pop up. Then, enter the amount of space to shrink.
    Shrink Volume Dialog

  • Click the Shrink button to confirm, then the disk will generate an unallocated space as follows:
    After Shrinking Partition

3. What can we do when Extend Volume is greyed out in Disk Management?

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:

Extend Volume option greyed out

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 at the right side of the partition that you want to extend. Because there is no "next contiguous unallocated space" at the right side the (C:) partition drive, so "Extend Volume" option is grayed out.

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

The only way is to delete the partition (here's D) between system drive and unallocated space. You can copy all data of D: partition to another partition or an external hard drive. After that, deleting D: partition so that the system partition can be enlarged with the "next contiguous unallocated space".

Note: Please try Windows Partition manager, AOMEI Partition Assistant to directly extend your system partition if contiguous unallocated space can not be generated.

4. Extending system boot partition

After deleting (D:) partition, you can extend system partition now. Select system partition C: drive, and then, right click on it and choose "Extend Volume...".

Extend Volume

After clicking "Extend Volume" option, it will pop out "Extend Volume Wizard" to help you finish the operation, the following screenshot is the new condition after expanding system partition:

After Extending System Volume

Now you will see the changes, the system boot partition (C: drive) has expanded from 20 GB to 149.89 GB.

Extending a partition or volume can be done via DiskPart.exe, or command line interface. This work can be done in both Vista, Windows Server 2008, Windows 7 and Windows 8. Start with the following steps:

  • Click Start and type CMD, then press Enter.

  • In the command prompt type

  • 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.
    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).

1). There must be some contiguous unallocated disk space after the partition that you want to extend by using Windows built-in Disk Manangement. If there is no contiguous unallocated space you can directly use the outstandingWindows partition manager to realize the expansion.

2). When no contiguous unallocated space, there are two ways of releasing 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.

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

4). Windows 2000/XP/2003 Disk Management does not support for extending partition and shrinking partition, only the Vista/2008/Win7/Win8 are able to extend volume and shrink volume on the basic disk.