How do I... resize a Vista partition without damaging data?

With Microsoft Windows Vista, resizing a partition that already contains data is not only possible, it's fairly simple. Jack Wallen shows you how it works.

There are many reasons why you might want or need to resize a partition, but generally speaking partitions cannot be resized without damaging data. That is, until Microsoft Windows Vista. With Vista, resizing a partition that already contains data is not only possible, it's fairly simple. The only gotcha involved is that Microsoft has, with good reason, obfuscated the process from the untrained eye.

Naturally I will give this warning. Although this method is tested and proven, that is not an absolute guarantee. Data can get lost when strange things occur. So with that in mind, your data is in your hands and you might want to do a data backup first.

With that being said, let's get going.

This download is also available in PDF format as a TechRepublic download.

Managing your drive

Microsoft hasn't placed the act of resizing a partition under a glaring spotlight for a reason. If the average user were to get their fingers on these tools, they could do some real, and irreversible, damage. Fortunately, you are not the average user.

Go to the Start menu and right-click on the Computer entry. When you do, you will see a menu you might not have even known was there (Figure A).

Figure A

If you click this entry, you can view drives and other components.
Once you click the Manage entry, the new window, Computer Management (Figure B) might take a while to appear.

Figure B

From this window there are a lot of administration tasks to undertake.
If the Storage entry isn't expanded, expand it to reveal the Disk Management tool. Now click on the Disk Management entry, which will show your hard disk layout (Figure C).

Figure C

Disk 0 is most likely your target disk.
What you now need to do is to choose the partition you want to resize and right-click the partition. Once you right-click the partition, you will see a new menu appear (Figure D). Depending on the setup of the drive you are changing, you may have more options available.

Figure D

You can also change the letter associated with your drive/partition.
Let's say you want to shrink a partition; select Shrink Volume to open the resizing window. What you will see is the amount of space available for resizing as calculated by Vista. As you can see in Figure E, Vista has calculated roughly 42GB available for resizing.

Figure E

Click the up or down arrows or enter the desired amount to set the size for shrinking.
Depending on the size of the change, the resizing of the partition can take some time. Once the partition has been successfully resized, the new partition will show up as unallocated space in the partition map (Figure F).

Figure F

You cannot simply delete a partition that has unallocated space.

If you want to expand a partition, there is a Wizard to walk you through that process. Click on the Expand entry in the right-click menu and the Wizard will start.

The Wizard will open to a window that allows you to delete a partition in order to make room for the expansion. As you can see in Figure G, there is a partition of 5006MB available to delete to make more room. Decide how much of that available space you want to use to expand the partition. Once you have set that size, click Next and then finalize the changes.

Figure G

You can expand a partition if you have room.

Final thoughts

It has been a long time coming to have on-the-fly partition resizing. This is one of the best features of Windows Vista. But as a final warning, do back up your data just in case.

TechRepublic's Windows Vista Report newsletter, delivered every Friday, offers tips, news, and scuttlebutt on Vista development, as well as a look at new features in the latest version of the Windows OS. Automatically sign up today!