This article explains the reasons why Extend Volume option grayed out in Disk Management and how to fix extend volume greyed out issue for Windows PC and Server.
Applies to: Windows 10, Windows 8, Windows 7, Windows Vista, Windows Server 2019, Windows Server 2016, Windows Server 2012 (R2), Small Business Server 2011, Windows Server 2008 (R2).
About Windows Extend Volume function
In old Windows XP and Server 2003, you can only do some basic operations in Disk Management such as create, delete and format partition. To change size of allocated partition, you need to run DiskPart command prompt. It is a bit difficult to most of personal computer users, thus, from Windows Vista, Microsoft added new Shrink Volume and Extend Volume functions with graphical interface. Windows Server 2008 and all subsequent versions inherited these two functions with same GUI.
As the name, Extend Volume is used to expand allocated partition without data loss, however, because of many limitations of this function, most of partitions can't be extended. Many people feedback that Extend Volume greyed out in Disk Management. Searching by Google and you'll see many similar complaints such as "Windows 10 won't let me extend volume", "extend volume is disabled for C drive", "extend volume option is grayed out and doesn't work".
This article introduces all possible reasons why Extend Volume option is grayed out and the corresponding solutions.
Why Extend Volume option greyed out in Windows PC & Server
There are 5 common reasons that why Extend Volume greyed out in Disk Management and I'll explain one by one.
Reason 1: No Unallocated space
Unallocated space is part of free disk space that is not used by any volume, it can be used to create new volume or combine into other ones. As we know, a 256GB physical hard disk drive can't be increased to 512GB. Therefore, before extending a partition, there must be Unallocated space on the same disk, otherwise, Extend Volume will be grayed out when you right click any drives in Disk Management.
There are 2 ways to get Unallocated space: delete and shrink volume.
- After deleting a volume, all disk space will be converted to Unallocated, all files in it will be deleted, too.
- After shrinking a volume, part of free used space will be converted to Unallocated, all files are still there.
Reason 2: Unallocated space is nonadjacent or on the left side
This is the most common reason why Extend Volume greyed out on both Windows Server and PC.
When shrinking a volume, the only option in Disk Management is entering an amount to shrink. You cannot choose to make Unallocated space on the left or right side of this partition. It is not an issue if you just want to decrease a partition, but if you want to extend a partition by shrinking another one, it is impossible in Disk Management, because Extend Volume only works when there's contiguous Unallocated space on the right.
As you see, there is 20GB Unallocated space generated after shrinking my D drive.
- When right clicking C: drive, Extend Volume is grayed out, because Unallocated space is nonadjacent to it. If Shrink Volume can make Unallocated space on the left side, there won't be such issue.
- When right clicking E: drive, Extend Volume greyed out, too, because Unallocated space is on the left side of it. If Disk Management can move Unallocated space to the right side, this problem can be solved.
The only way to enable Extend Volume for drive C is by deleting the adjacent drive D. But to drive E, there is no way in Disk Management.
Do NOT delete drive D if you installed programs into it, and remember to transfer files first if you can delete it.
Reason 3: Unsupported file system
Both Shrink and Extend Volume functions only support the partition that are formatted as NTFS or without file system (RAW). Thus, if you right click FAT32 or any other types of partitions, Extend Volume option is grayed out.
In my test computer, there is 59.46GB Unallocated space that is adjacent and on the right side, but drive D is FAT32, so Extend Volume doesn't work.
Reason 4: Restriction between Primary and Logical partition
In GPT style disk, all partitions are created as Primary, but in MBR disk, there could be both Primary and Logical partition. Unlike Primary partitions that work as independent unit, Logical Partition is part of the Extended partition. Extended partition works like a container and the disk space of Logical partition will be converted to Free after deleting.
Free space deleted from Logical drive can't be extended to any Primary partition, Unallocated space deleted from Primary partition can't be extended to any Logical drive.
Reason 5: 2TB limitation in MBR disk
Nowadays, hard disks are much larger and it is common to use 2TB+ disk for personal computers. To a server, it is common to use over 10TB RAID array via several large disks. But if you initialized the disk as MBR, you can use only 2TB space, the remaining space can be created new or added to other volume in Disk Management.
As the screen shot shows, drive H is formatted as NTFS and there is right contiguous Unallocated space, but Extend Volume still greyed out. When I right click this Unallocated space in Disk Management, all options are grayed out.
What to do when Extend Volume greyed out in Disk Management
Steps to fix Extend Volume greyed out issue in Disk Management (for both Windows Server and PC):
- Download NIUBI Partition Editor and find out your disk partition configuration (structure).
- If Extend Volume greyed out because of nonadjacent Unallocated space, follow the steps in the video to move Unallocated space and then combine to other volume:
- If Extend Volume grayed out of because of non-supported FAT32 partition or the restriction between Primary and Logical partition, follow the steps to shrink and extend partition.
- If Extend Volume greyed out because of 2TB limitation in MBR disk, follow the steps in the video to convert MBR disk to GPT and then extend this volume.
As a disk partition management toolkit, NIUBI Partition Editor helps you do many other operations. There's free edition for Windows 10/8/7/Vista/XP home computer users (100% clean without any bundles).