Windows 11 Can't extend the C: drive, have unallocated space remained

chief89

Member
Joined
May 18, 2026
Messages
1
Hi, I deleted my D: partition and its now unallocated but still (Extend Volume) is grayed out.

Windows Disk Management showing C: and 232.69 GB unallocated space.
 

Solution
Hi chief89 — your screenshot explains it.
The reason Extend Volume is greyed out is that Windows Disk Management can only extend a partition into unallocated space directly to its right. In your layout, the 777 MB Recovery partition is between C: and the unallocated space:
EFI | C: | Recovery | Unallocated
So C: cannot be extended until that Recovery partition is moved or removed.

Best options​

Option 1 — Safest/easiest: move the Recovery partition​

Use a partition manager that can move partitions, such as:
  • AOMEI Partition Assistant
  • MiniTool Partition Wizard
  • GParted Live USB
Steps:
  • Back up important files first.
  • If BitLocker is...
Hi chief89 — your screenshot explains it.
The reason Extend Volume is greyed out is that Windows Disk Management can only extend a partition into unallocated space directly to its right. In your layout, the 777 MB Recovery partition is between C: and the unallocated space:
EFI | C: | Recovery | Unallocated
So C: cannot be extended until that Recovery partition is moved or removed.

Best options​

Option 1 — Safest/easiest: move the Recovery partition​

Use a partition manager that can move partitions, such as:
  • AOMEI Partition Assistant
  • MiniTool Partition Wizard
  • GParted Live USB
Steps:
  • Back up important files first.
  • If BitLocker is enabled, suspend it first.
  • Open the partition tool.
  • Move the 777 MB Recovery partition all the way to the far right of the disk.
  • Extend C: into the newly adjacent unallocated space.
  • Apply changes and reboot if prompted.
Expected final layout:
EFI | C: | Recovery
This keeps the Windows Recovery Environment intact.

Option 2 — Built-in Windows method: delete the Recovery partition​

Warning: This removes the recovery partition temporarily. Make a backup first. Also create a restore point before doing this.
  • Open Command Prompt as Administrator.
  • Check WinRE status:
reagentc /info
  • Disable WinRE:
reagentc /disable
  • Start DiskPart:
diskpart
  • Select the disk and recovery partition:
Code:
list disk
select disk 0
list partition
select partition 4
delete partition override
exit
  • Open Disk Management again.
  • Right-click C:.
  • Choose Extend Volume.
  • Extend into the unallocated space.
After that, re-enable Windows Recovery:
Code:
reagentc /enable
reagentc /info
If reagentc /enable fails, tell us the exact error message before doing anything else.

My recommendation​

Since you appear to have plenty of unallocated space and only a small Recovery partition blocking it, the cleanest approach is:
Use a partition tool to move the 777 MB Recovery partition to the end, then extend C:.
That avoids deleting recovery tools and is usually simpler than rebuilding WinRE manually.
Please also confirm whether BitLocker/device encryption is enabled before you resize anything.
 

Solution
Hi, I deleted my D: partition and its now unallocated but still (Extend Volume) is grayed out.

View attachment 144713
You can check if there's a small Recovery or EFI partition sitting between C: and that 232.69 GB of unallocated space. Windows can only extend C: when the unallocated space is directly beside it so if another partition is in the way Extend Volume stays grayed out. Also if your deleted D: drive had important files don't make any disk changes yet. You can use data recovery software like Stellar Data Recovery to scan the unallocated space and recover files before extending or creating partitions.
 

Back
Top