How-to shrink a volume (drive or partition) in Windows Vista, create a new volume from the unallocated (empty) space created, and then format the new volume.
Introduction
This guide shows you how to take your C: drive, for instance, that has lots of extra space and shrink it. You can use the extra space created by shrinking the C: drive and use it to create a new volume (drive or partition) that could be used for backup or many other purposes.
Before you shrink a volume you should know that there’s a risk of a loss of data or a total crash, although it’s very small. It’s a good idea to backup your computer before you shrink a volume.
Shrink a Volume
- Right-click Computer in the Start Menu and then select Manage.
- Click on Disk Management under Storage in the left column of the Computer Management window.
- Right-click the volume you want to shrink and then select Shrink Volume.
- Enter the amount of space (in MB) you want to shrink the volume by in the Shrink window. Make sure you leave extra space, especially on the C: (or system) drive.
Note: 1024MB is equal to 1GB.
- Click Shrink to start the shrinking process.
- When it’s done you’ll have a bunch of unallocated space to work with.
Format the New Unallocated Space
Not that you’ve shrunk a volume and created some empty (unallocated) space, you need to create a new volume from the empty space you’ve just created, and then format it before you can use it.
- Right-click the unallocated space you’ve just created in disk management, and then select New Simple Volume.
- Click Next in the welcome screen.
- In this example I’m using all available space to create a new simple volume. Leave the new simple volume size like it is and click Next.
- In this example I’m assigning a drive letter to this new simple volume and I’m also letting Windows Vista pick the letter. Make sure the drive letter is not taken. If it is, change it to an untaken letter. Leave the settings like they are and click Next.
- I strongly suggest formatting the drive in NTFS with the default Allocation unit size. You can name the new volume whatever you like. Click Next.
- Click Finished confirming what you want to do and the empty space will be turned into a new formatted volume.
After following all the steps above you should now have a smaller volume (drive, or partition) you shrunk and a new volume consisting of unallocated space created by shrinking the first volume.
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thanks a lot for your instruction
I tried new simple volume: It says it already contains maximum number of partitions, you cannot create new volume? What to do now?
I’ve try it successfully! I recommend it to everyone
does NOT work. The “shrink” button never is active.