This article introduces why Extend Volume greyed out in Windows Server 2008 R2 Disk Management, and what to do when Extend Volume is disabled.
The longer the server is running, the higher probability disk partition runs out of space, especially to system partition C. It can't be better if you can extend C: drive without starting over or wasting a long time to back up and restore everything. In previous Server 2003, you can extend partition via DiskPart command prompt. To make it easier, Microsoft adds new GUI Extend Volume function in Server 2008 Disk Management tool.
In most of server machines, there is another volume such as D on the same hard disk, so some people try to shrink D to extend C drive but failed. Searching by Google, you'll find that many people encountered the same problem that Extend Volume greyed out in Windows Server 2008 Disk Management. To many server administrators, this problem is annoying. This article introduces the reasons why Windows Server 2008 Extend Volume option is grayed out and what to do.
1. Why extend C drive greyed out in Windows 2008 Server
Most of server administrators encounter problem when extending C drive, so firstly I'll introduce why Extend Volume greyed out for C drive in Windows Server 2008 and R2. There are 2 common reasons and I'll introduce one by one.
Reason 1. No adjacent Unallocated space on the right
First of all, you should know that the size of a physical hard disk is fixed, a 250GB disk can't be decreased to 200GB or increased to 500GB. Before extending a partition, there must be free Unallocated space on the same disk.
If you delete a partition, all files in it will be deleted, too. But if you shrink this partition, all files will keep intact and only part of free space will be converted to Unallocated. In addition, if this partition is used for programs or some Windows services, it can't be deleted.
So many people try to make Unallocated space by shrinking partition. But as you see, Extend Volume still greyed out for C and E: drive after shrinking partition D. This is because:
Unallocated space that shrunk from D is nonadjacent to C drive and E: is on the right side, so Extend Volume is disabled. This is the most common reason why extend C drive greyed out in Windows Server 2008 Disk Management.
Reason 2. Different partition type
Some people are wondering if it is possible to enable Extend Volume by deleting the right contiguous partition (D:). Yes to GPT disk, but to MBR disk, it depends.
System C: drive is always Primary, if the right contiguous partition D (E in some servers) is Logical, Extend Volume still greyed out for C drive after deleting D.
In Windows Disk Management, Unallocated space that 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 that deleted from a Logical drive is still part of the Extended partition, to convert it to Unallocated, you must delete all other Logical drives and the entire Extended partition. Obviously, it is a bad idea.
2. Why extend volume greyed out in Windows Server 2008 R2
To data volume, there are 2 additional reasons why Extend Volume greyed out in Server 2008 Disk Management.
Reason 1. Unsupported file system
From Microsoft explanation, Extend Volume can only expand the partitions that are formatted with NTFS or without file system (RAW).
Another common FAT32 as well as any other types of partitions are not supported.
To show you this limitation, I converted D drive to FAT32, as you see, both Shrink and Extend Volume are grayed out, although there is adjacent Unallocated space on the right.
Reason 2. 2TB limitation on MBR disk
Nowadays, hard disks are much larger and it is common to use 2TB+ physical disk or over 10TB RAID array on a server. The problem is, if you initialized the disk as MBR, you can use only 2TB space, the remaining space can't 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 contiguous Unallocated space on the right side, but Extend Volume still greyed out.
In this case, when you right click the Unallocated space in Disk Management, all options are grayed out.
What to do when Extend Volume option is grayed out/disabled
It seems a bit complicated, but it is very easy to solve these problem with NIUBI Partition Editor. Firstly, check your server disk partition structure and find out the reason why Extend Volume greyed out, then follow the corresponding solution below.
Solution 1. Move Unallocated space next to C drive
If you have shrunk drive D (or E) to get Unallocated space with Disk Management, NIUBI Partition Editor can move partition D to right side, then Unallocated space will be to contiguous to C drive.
Download this program and you'll see the main window with disk partition layout and other information. There is 20GB Unallocated space in Disk 0 which is shrunk from drive D.
Steps to fix Extend Volume greyed out in Windows Server 2008 R2 with NIUBI:
Step 1: Right click D: drive and select "Resize/Move Volume", drag the middle 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. (All operations before this step only work in virtual mode)
Solution 2. Resize partition with NIUBI Partition Editor
If you want to extend a FAT32 partition, or extend a Primary partition by shrinking a Logical drive (and vice versa), follow the steps in the video to resize partition with NIUBI:
Solution 3. Convert MBR disk to GPT before extending
If you want to extend a partition to 2TB+ or use 2TB+ space on a MBR disk, you need to convert MBR to GPT in advance, follow the steps in the video:
Besides shrinking, moving and extending partition to fix Extend Volume greyed out issue in Windows Server 2008/2012/2016/2019, NIUBI Partition Editor helps do many other disk partition management operations such as merge, copy, wipe, hide, defrag, scan partition.