This article introduces why cannot extend volume in Windows Server 2008 R2 Disk Management or via diskpart, and what to do if unable to extend server 2008 partition.
Why cannot extend volume in Server 2008 Disk Management
Better than previous Windows Server 2003, Server 2008 native Disk Management provides new Shrink Volume and Extend Volume GUI functions to help change partition size without losing data. When a server runs out of space, it can't be better if you can extend disk partition without wasting a long time to recreate partitions and restore everything from backup. However, many people feedback that they cannot extend volume in Server 2008 Disk Management, because Extend Volume option is disabled.
There are several reasons why can't extend volume in Windows Server 2008 Disk Management.
① No right adjacent Unallocated space
The size of a physical hard disk is fixed, a 500GB disk can't be decreased to 250GB or increased to 1TB. Therefore, before extending a hard drive partition, there must be free Unallocated space.
Although there is Shrink Volume function to decrease partition, it can only make Unallocated space on the right. This space can't be extended to the right contiguous or any nonadjacent partitions with Extend Volume function.
As you see in my server, the 20GB Unallocated space is shrunk from D drive, Disk Management cannot extend volume C: and E: with this space.
If you want to extend partition C with Server 2008 Disk Management, you must delete the adjacent D: drive. If there is no or you cannot delete the right contiguous partition, Disk Management is completely useless.
② File system is not supported
From Microsoft explanation, Extend Volume can only expand the partitions that are formatted with NTFS or without file system (RAW).
As you see in the screenshot, drive D is FAT32, both Shrink and Extend Volume are grayed out, although there is adjacent Unallocated space on the right.
③ Different partition type
Cannot get adjacent Unallocated space by shrinking volume, some people are wondering if it is possible to delete the right adjacent partition to enable Extend Volume. It works on GPT disk, but on MBR disk, it depends.
For example, if both C and D drive are Primary partition, it works by deleting D. But if drive D is Logical, Extend Volume is still disabled for C drive after deleting it.
In Server 2008 Disk Management, Unallocated space deleted from Primary partition can't be extended to any Logical drive. Free space deleted from Logical drive can't be extended to any Primary partition.
Free space is still part of the Extended partition, to convert it to Unallocated, you have to delete all other Logical drives and the whole Extended partition.
Why cannot extend partition via diskpart command
Diskpart has no graphic dialog box, it works via command prompt. In diskpart command window, input help extend, then you'll see the introduction and restrictions.
- The partition that you want to extend must be formatted with NTFS or without file system (RAW).
- The free (Unallocated) space must be adjacent and on the right side of the partition that you want to expand.
- Free (Unallocated) space and the partition must be on the same disk.
Better than Disk Management, diskpart can extend C drive by deleting D even if D is Logical drive.
What to do when unable to extend volume for Windows 2008 server
In most cases, ① is the reason why unable to extend partition volume in Windows 2008 server with diskpart command or Disk Management. To solve this problem, you need to run NIUBI Partition Editor and move Unallocated space next to C drive.
Download NIUBI Partition Editor and you'll see the main window with disk partition structure and other information.
Solution when cannot extend volume/partition in Windows Server 2008 R2:
Step 1: Right click the right adjacent partition (D:) and select "Resize/Move Volume", drag middle position towards right in the pop-up window.
Step 2: Right click C: drive and select "Resize/Move Volume" again, drag right border towards right in the pop-up window.
Step 3: Click Apply on top left to execute.
If you have not shrunk a partition to get Unallocated space, shrink with NIUBI Partition Editor. It is able to make Unallocated space on the left while shrinking partition. To this software, there's no difference to shrink and extend NTFS or FAT32 partition, Primary or Logical partition. You just need to drag and drop on the disk map, follow the steps in the video:
If you use any types of hardware RAID array, or run Server 2008 in VMware/Hyper-V, there's no difference and just follow the steps in the video.
Better than other tools, NIUBI Partition Editor has unique 1 Second Rollback, Virtual Mode, Cancel-at-well technologies and advanced moving algorithm to help repartition hard drive safely and much faster. It also helps you do many other disk partition management operations.