This article introduces why Extend Volume greyed out in Windows Server 2012 R2 Disk Management, and what to do when Extend Volume option is grayed out for C: or D: drive.
Microsoft provides many built-in utilities to manage server, to manage storage device, there is Disk Management component, which is installed by default. In Windows Server 2012 Disk Management, you can create, delete, format volume and change drive letter. Besides the basic management operations, you can change partition size with Shrink Volume and Extend Volume functions.
Extend Volume can extend system partition and data volumes without losing data. However, it has many limitations and works under very restricted condition. Thus, many people feedback that Extend Volume greyed out in Windows Server 2012 (R2) Disk Management.
Why Extend Volume greyed out in Server 2012 DM
There are many reasons why Extend Volume is disabled in Windows Server 2012 Disk Management, I'll show you one by one.
Reason 1: No Unallocated space
Hard disk is physical unit and the size is fixed. Before extending a partition, there must be Unallocated space. Otherwise, a 500GB disk will be increased to 1TB, it is possible.
So, if you right click a volume without Unallocated space, of course Extend Volume is grayed out.
To get Unallocated space, you may either delete or shrink other volume.
Reason 2: Unallocated space is nonadjacent
This is the most common issue encountered by server administrators.
Shrink Volume can only make Unallocated space on the right side while shrinking a partition, but this Unallocated space can only be combined to the left contiguous partition via Extend Volume.
As you see, Extend Volume greyed out for drive C: and E: after shrinking D.
Reason 3: Partition is not supported
From Microsoft explanation, Extend Volume function only support expanding the partitions that are formatted as NTFS or without file system (RAW).
If this partition is FAT32 or any other types, Extend Volume is grayed out, although there is right adjacent Unallocated space.
Reason 4: Free space can't be extended to Primary partition
In almost all servers, system partition C is NTFS and Primary. If the right contiguous volume D is Logical partition, you still cannot extend C: drive even by deleting D.
Different with Unallocated space that is not belonged to any partition, Free space is still part of the Extended partition. To convert it to Unallocated, you must delete all other Logical and the entire Extended partition.
As you see, disk space of D is shows as Free and Extend Volume greyed out for C: drive after deleting D.
Reason 5: Unallocated space can't be extended to Logical partition
Similarly, Unallocated space deleted from a Primary partition cannot be extended to any Logical partition via Server 2012 Disk Management.
How to enable Extend Volume option
If you have got Unallocated or Free space by shrinking the adjacent drive D, you just need 1 step to move the space to the left side, then Extend Volume will be enabled for C drive.
Download NIUBI Partition Editor and you'll see the main window with disk partition structure and other information. There is 20GB Unallocated space that is shrunk from D drive via Disk Management.
Steps to fix Windows Server 2012 Extend Volume greyed out issue:
Step 1: Right click drive D: and select "Resize/Move Volume", drag middle position towards right in the pop-up window:
Step 2: Right click drive C: and select "Resize/Move Volume" again, drag right border towards right in the pop-up window.
Step 3: Click Apply on top left to take effect to real disk partition. (The operations before clicking Apply just work in virtual mode.)
Solution to fix Extend Volume grayed out issue
When there is contiguous Unallocated/Free space on either side of the drive that you want to extend, you can combine it with NIUBI Partition Editor by 1 step, no matter this partition is NTFS or FAT32, Logical or Primary partition. If Unallocated space is nonadjacent, you can move and then combine it.
Watch the video how to fix Extend Volume greyed out in Windows Server 2012:
When Extend Volume option is grayed out in Windows Server 2012 Disk Management, find out the reason and use corresponding method. Besides shrinking, moving and extending partition, NIUBI Partition Editor helps you merge, copy, convert, hide, wipe, defrag, scan partition and much more.