On basic GUID partition table (GPT) disks, assigns the GPT attribute(s) to the partition with focus.

For examples of how this command can be used, see Examples.


gpt attributes=<n>


Parameter Description


The hexadecimal that pertains to the attribute that you want to apply to the partition with focus. The GPT attribute field is a 64-bit field that contains two subfields. The higher field is interpreted only in the context of the partition ID, while the lower field is common to all partition IDs.



Changing the GPT attributes might cause your basic data volumes to be unmountable or fail to be assigned drive letters. Unless you are an original equipment manufacturer (OEM) or an IT professional experienced with GPT disks, do not change GPT attributes.

  • GPT partition attributes give additional information about the use of the partition. Some attributes are specific to the partition type GUID.

  • All partitions have the following attribute: 0x0000000000000001. This marks the partition as a required partition. It indicates to all disk management utilities that the partition should not be deleted.

  • The EFI System partition contains only those binaries necessary to start the operating system. This makes it easy for OEM binaries or binaries specific to an operating system to be placed in other partitions.

  • For basic data partitions, the following attribute can be defined: 0x8000000000000000. It prevents the partition from having a drive letter automatically assigned. By default, each partition is assigned a new drive letter. Setting this attribute ensures that when a disk is moved to a new computer, a new drive letter will not be automatically generated. Instead, the user can manually assign drive letters.

  • Other attributes can be added at any time.

  • A basic GPT partition must be selected for this operation to succeed. Use the select partition command to select a basic GPT partition and shift the focus to it.


If you are moving a GPT disk to a new computer and would like to prevent that computer from automatically assigning a drive letter to the basic GPT partition with focus, type:

gpt attributes=0x8000000000000000

Additional references