Windows 7: Partition or Volume - Shrink

   Information

This will show you how to shrink an existing partition or volume using Disk Management or Diskpart in Windows 7 to create unallocated disk space, from which you can create a new partition or volume with.

   Warning

You must be logged on in an administrator account to be able to do this tutorial.

If while shrinking a partition below, you get a Convert to Dynamic disks? type prompt, do not do so.

If you disable the Disk Defragmenter service, then you will get the error below when you try to do anything in Disk Management. If you get this error, then make sure that the Disk Defragmenter service is set to only Manual.

OPTION ONE

Using Disk Management

1. Open the Control Panel (icons view), and click on the Administrative Tools icon. then close the Control Panel window.

2. Click on Computer Management in Administrative Tools, then close the Administrative Tools window.

3. In the left pane under Storage, click on Disk Management. (See screenshot below)

4. In the middle pane, right click on the partition that you want to shrink and click on Shrink Volume. (See screenshot above)

5. Type in how many MB (1 GB = 1024 MB) of the available shrink space shown that you want to shrink the partition or volume by to be used for the new unallocated space, then click on the Shrink button. (See screenshot below)

   Warning

The size of the available shrink space can be restricted by the amount of space currently allocated to on the hard drive for the virtual memory page file, System Protection maximum storage space size, and hibernation files. The location of the files on the hard drive plays a big part here because these files are marked as unmovable, and Disk Management is unable to relocate them. As such, if these unmovable files are located in the middle of the total amount of free space on the disk, then only the amount of free space on the other side (to the right) of these files will actually be available for the new partition. This will result in you showing that you have x amount of free space, but not being able to use it for your partition. The only way around this is to use a 3rd party hard drive partition management program, or setup the partition when installing Vista.

6. The selected partition (step 4) has now been shrunk to create a new empty unallocated space. You can use this new unallocated space to create a new partition with. (See screenshot below)

7. Close the Computer Management window. (See screenshot above)

OPTION TWO

Using Diskpart in a Elevated Command Prompt

1. Open a elevated command prompt, or a command prompt at boot.

2. In the elevated command prompt, type diskpart and press Enter. (See screenshot below)

3. In the elevated command prompt, type list volume and press Enter. (See screenshot below)
NOTE: This will give you a list of volume numbers to select from to shrink.

4. In the elevated command prompt, type select volume # and press Enter. (See screenshot below)
NOTE: You would substitute # for the volume number listed that you want to shrink. For example, I want to shrink the listed volume 2, so I would type select volume 2 and press Enter.

5. In the elevated command prompt, type shrink querymax and press Enter. (See screenshot below)
NOTE: This will give you the maximum amount of size in MB that you can shrink the selected partition or volume (step 4) by to be used as the new unallocated space. For example, I have 696 GB available to shrink.

6. To Shrink All of the Available Space

A) In the elevated command prompt, type shrink and press Enter.
NOTE: This will shrink the selected partition or volume by all of the maximum number of reclaimable bytes (step 4) to be used for the new unallocated space.

B) Go to step 8.

7. To Shrink the Available Space by a Specified Size

A) In the elevated command prompt, type shrink desired=(# in MB) and press Enter. (See screenshot below)
NOTE: You would substitute (# in MB) for how many MB (1 GB = 1024 MB) you want to shrink the selected partition or volume (step 4) by to be used for the new unallocated space. For example, if I only wanted to shrink the partition or volume by 81920 MB (80 GB), then I would type shrink desired=81920 and press Enter.

8. In the elevated command prompt, type exit and press Enter. (See screenshot below)

9. Close the elevated command prompt.

10. The selected partition (step 4) has now been shrunk to create a new empty unallocated space. You can use this new unallocated space to create a new partition with.