How to Delete OEM Recovery Partition Using Diskpart

Most desktop or laptop manufacturers create a separate recovery partition on hard drives of their branded OEM systems to store a reference system image (you can roll back to it, when doing factory reset) and a number of system and diagnostic tools provided by the manufacturer. The size of the partition can be up to several tens of gigabytes. In some cases, it is worth to remove such an OEM/EISA partition and increase the system partition .

It is convenient to create/delete partitions using Disk Management (diskmgmt.msc) snap-in. In this example, the 15 GB recovery partition has volume label Recovery and type OEM Partition. If you right-click the OEM Recovery partition in Disk Management, you can see that there is no disk menu (and the option to remove the partition as well).

Microsoft has deliberately restricted Disk Management functionality to work with  system, protected, hidden or OEM recovery partitions. To deal with these types of partitions, you have to use third-party tools or the integrated utility diskpart. In this example we’ll show how to delete an OEM recovery partition from your hard drive using diskpart.

Start the command prompt with the administrator privileges and run the following command:

diskpart

Display the list of the disks in the system:

DISKPART> list disk
Disk ###  Status         Size     Free     Dyn  Gpt
--------  -------------  -------  -------  ---  ---
Disk 0    Online          59 GB      5120 KB

Select the disk containing the partition you need:

DISKPART> select disk 0

Disk 0 is now the selected disk.


Display the list of available partitions on the selected disk:

DISKPART> list partition

Partition ###  Type              Size     Offset
-------------  ----------------  -------  -------
Partition 1    Recovery          400 MB  1024 KB
Partition 2    System (EFI)      260 MB   401 MB
Partition 3    Reserved          128 MB   661 MB
Partition 4    Primary            43 GB   789 MB
Partition 5    Recovery          495 MB    43 GB
Partition 6    Primary            15 GB    44 GB

Then select the partition you want to delete:

DISKPART> select partition 6

Partition 6 is now the selected partition.

Let’s try to delete this partition:

DISKPART> delete partition

The following error appears:

I. e., diskpart cannot delete this partition.

Display the detailed information about the selected partition:

DISKPART> detail partition

Partition 6
Type : 27
Hidden: Yes
Active: Yes
As you can see, the type of the partition is set to 27, while common Windows NT NTFS partition with the standard MBR partition table uses type 07 (a hidden partition has the code 17).

You may try to change the partition type as follows:

DISKPART>setid id=07

However, it’s easier to delete the partition using override flag, that enables any partition type to be deleted:

DISKPART> delete partition override

DiskPart successfully deleted the selected partition.

Now you may close the diskpart session using commandexit

Using this method, you can delete any OEM or EFI partition. After it is deleted, the free space may be used to enlarge the existing partition or create a new one in Disk Management.