Cannot extend C drive in Windows Server 2012 (R2) Disk Management
From Windows Server 2008, Microsoft provides GUI function in Disk Management to change partition size. It is great improvement to previous editions. With Shrink Volume function, you can decrease an existing partition without reboot. Extend Volume helps you easily increase a partition size. However, many people try to shrink D drive, but found they cannot extend C drive, because Extend Volume is greyed out. In this page, I’ll tell why you cannot extend C drive in Windows Server 2012 (R2) Disk Management, and how to solve this problem in an easy way.
Scenarios of cannot extend C drive
The reason why so many people encountered this problem is because Extend Volume function disabled in most cases. Here I’ll show one by one.
Right-click Windows and click Disk Management.
1. Right click C drive directly, Extend Volume is grayed out.
2. Shrink the adjacent drive D and retry.
Shrink 10GB space.
Right click C drive, Extend Volume is still disabled.
3. Delete drive D and retry.
You cannot extend C drive, too.
4. Delete all volume in the Extended partition and retry.
Delete the Extended partition.
Now, Extend Volume becomes available.
As I said above, you cannot extend C drive in Windows Server 2012 in most cases.
Why cannot extend C drive in DM
There are 3 main reasons why you cannot extend C drive with Extend Volume function:
- You may use FAT32 file system. From Microsoft explanation, only NTFS and RAW format partition can be extended.
- There is no adjacent Unallocated space. Only when the Unallocated space is adjacent and at right side of C drive, you can expand C drive with the Unallocated space.
- You did not delete the adjacent Extended Partition. If the adjacent drive D is in the Extended Partition, you cannot extend C drive by simply deleting D. You should delete all volumes in the Extended Partition and then delete the entire Extended Partition.
Extend C drive without deleting
With 3rd-party server partition software, it is much easier to decrease and increase partition size. You can extend C drive without deleting. As long as there is free space in any other drives in the same disk, you can take free space out and add to C drive easily.
Firstly, let’s open Disk Management:
As you see, C drive is 39.66GB and the 10GB Unallocated space (shrank from D) is behind D:.Download and launch NIUBI Partition Editor, the disk partition layout is the same with Disk Management.
Step 1: Right click drive D and select “Resize/Move Volume“.
Step 2: In the pop-up window, drag middle position rightwards.
Click OK and back to the main window, where the 10GB Unallocated space moved to behind C: drive.
Step 3: Right click C drive and select “Resize/Move Volume” again. In the pop-up window, drag the right border rightwards to hold the Unallocated space.
Step 4: Click OK and back to the main window, where the 10GB Unallocated space added into C drive. Click Apply on top left to execute, done.
Check in Disk Management:
C drive increased to 49.66GB.
The most possible reason why you cannot extend C: drive in Server 2012 is because Extend Volume grayed out, so you cannot extend C drive after shrinking D. In this situation, run NIUBI Partition Editor to move the Unallocated space to behind C: drive and then you can expand C drive easily.
NIUBI Partition Editor integrated unique Roll-Back protection technology, which is able to roll back the server to the status before reszing automatically and rapidly if power failure or any other hardware issue occur, so you don’t need to worry about Operating System and all data safety. Furthermore, it is 30% – 300% faster than ANY other tools, because of its unique file-moving algorithm.