Usually, you can easily delete a partition in Disk Management. But you can't delete EFI system partition in Windows because the "Delete Volume" feature is grayed out.
The "Delete Volume" may also gray out when you try to delete the OEM partition, recovery, or system reserved partition. This page will talk about how to delete the EFI system partition on Windows, as well as the must-know information about the EFI system partition, including what EFI is and what happens when the partition is deleted.
To efficiently remove EFI partition from your computer, you can fully trust Qiling partition manager software as shown in Part 3. Keep reading and learn more details.
EFI partition, also known as EFI system partition, short for ESP, is automatically generated when you successfully install Windows OS on a GPT disk in your computer. It takes about 100M or 200MB or so with no drive letter. Normally, you may see more EFI system partition on Windows 10.
According to Wikipedia, "EFI system partition (ESP) is a partition on a data storage device which is used computers adhering to UEFI (Unified Extensible Firmware Interface). When a computer is booted, UEFI firmware loads files stored on the ESP(EFI system partition) to start installed operating system and various utilities."
It includes 4 main components:
According to Part 1, the EFI partition is like an interface for the computer to boot Windows off. It's a pre-step that must be taken before running the Windows partition. Without the EFI partition, your computer won't be able to boot into Windows.
In a word, EFI system partition deletion will cause the installed system unbootable. Therefore, EFI system partition is usually protected and locked by the Windows operating systems to prevent and avoid accidental deletion. That's why you can't see the EFI partition in Windows File Explorer nor delete it using Windows Disk Management.
For users who want to delete the EFI system, there are two methods available. One is to delete with the Windows built-in tool - Diskpart and the other is to apply a simple third-party tool - Qiling Partition Master. To avoid unnecessary file loss, make sure you have backed up the ESP files in advance.
Besides DiskPart, third-party partition manager software works more flexibly and reliable in dealing with this issue. Professional partition manager software - Qiling Partition Master simplifies the process of deleting EFI partitions in Windows as easy as 1-2-3.
Now download Qiling Partition Master and learn the detailed guide.
Step 1. To delete a system involved partition like the EFI system partition, you'll be asked to operate in a WinPE environment. So first of all, use the feature of "WinPE Creator" in Qiling Partition Master to create a bootable USB drive to start. Click to get the full guide on how to create and access Qiling WinPE bootable disk.
Step 2. Open Qiling Partition Master WinPE edition. Click on the EFI system partition and choose "Delete".
Step 3. Click "OK" to confirm the message "Are you sure you want to delete the selected partition?".
As a command-line utility, DiskPart is sort of complex for average users to apply. Please be very careful while following the below command lines to delete EFI partition:
Step 1. Open DiskPart on your PC.
Step 2. Change EFI system partition ID and set it as a data partition.
Type the below command lines and hit Enter each time:
By doing so, it will make the EFI system partition deletable. Continue with the following steps to remove this partition on your hard drive.
Step 3. Delete the EFI partition with the command line.
Type the below command lines and hit Enter each time:
Step 4. Complete EFI deleting process.
Finally, type "exit" to close the windows when you receive the message that says, 'DiskPart successfully deleted the selected partition'.
When you've successfully deleted the EFI partition on your PC, you can create a new partition with the unallocated space to use as a data partition or add the free space to other existing partitions.
The following tutorial shows how to partition a hard drive with Qiling Partition Master. You can learn how to resize a partition, create a partition, and delete the partition.
If you are having some more questions about EFI partitions, you may refer to the below links for help: