Sets attributes of a partition, such as active, read-only, and offline states.
Windows Server · Risk: High · Documentation Verified
Last verified: 2026-10-26
Microsoft Storage reference: Sets attributes of a partition, such as active, read-only, and offline states. The syntax and selected example below are adapted from the pinned Windows Server 2025 reference. Module availability, target configuration and delegated permissions determine whether it can run in your environment. Documentation and parameter text: Microsoft, CC BY 4.0; formatting adapted by Cmdlet World. No execution testing is claimed.
Use an account with the target resource permissions documented for Set-Partition. Modifying administrative cmdlets may require elevation or delegated administration. This catalog does not assert that ordinary users can execute the command.
Supported environments
Windows / Storage · Windows Server 2025 documentation; feature/module prerequisites apply
Parameters
-AsJob
Runs the cmdlet as a background job. Use this parameter to run commands that take a long time to complete.
-CimSession
Runs the cmdlet in a remote session or on a remote computer. Enter a computer name or a session object, such as the output of a New-CimSession or Get-CimSession cmdlet. The default is the current session on the local computer.
-Confirm
Prompts you for confirmation before running the cmdlet.
-DiskId (required)
Specifies the disk ID of the partition to modify.
-DiskNumber (required)
Specifies an array of disk numbers. These represent the disks on which the partitions reside to modify.
-DriveLetter (required)
Specifies the drive letter of the partition to modify.
-GptType
Sets the type of a GPT partition to a specific GUID.
-InputObject (required)
Specifies the input object that is used in a pipeline command.
-IsActive
Specifies that the partition is marked as active and can be used to start the system. This parameter is only relevant for MBR disks.
-IsDAX
Formats a volume as a DirectAccess (DAX) volume. DAX provides applications with direct access and byte-addressability options via memory mapping on storage class memory (SCM) devices, such as NVDIMM-N. If you do not specify the *IsDAX* parameter, the cmdlet defaults to a regular, non-DAX volume.
-IsHidden
Specifies that the partition is hidden. As a result, the partition does not receive a drive letter, does not receive a volume GUID path, and does not host volume mount points. This ensures that applications such as disk defragmenter do not access the partition.
-IsOffline
Takes the partition offline until explicitly brought back online, or until an access path is added to the partition.
-IsReadOnly
Sets the partition to be read-only (IsReadOnly $true) or read-write (IsReadOnly $false).
-MbrType
Sets the type of an MBR partition to a specific numeric ID.
-NewDriveLetter
Specifies the new drive letter for the partition.
-NoDefaultDriveLetter
Specifies that the automatic assignment of a drive letter is disabled. This is only honored for GPT disks. This attribute is useful in storage area network (SAN) environments.
-Offset (required)
Specifies the partition's offset from the beginning of the disk, measured in bytes.
-PartitionNumber (required)
Specifies the number of the partition.
-ThrottleLimit
Specifies the maximum number of concurrent operations that can be established to run the cmdlet. If this parameter is omitted or a value of 0 is entered, then Windows PowerShell® calculates an optimum throttle limit for the cmdlet based on the number of CIM cmdlets that are running on the computer. The throttle limit applies only to the current cmdlet, not to the session or to the computer.
-WhatIf
Shows what would happen if the cmdlet runs. The cmdlet is not run.
Prerequisites
Windows with the Storage module and the Windows feature or management tools that provide it. Confirm target connectivity and version compatibility using the linked Microsoft reference.
Security considerations
This cmdlet changes system state. Review every target and parameter in the official reference, test outside production, and prepare an appropriate backup or rollback. Do not execute the example automatically.
Examples
Example 1: Set the partition to read-only
Set-Partition -DriveLetter Y -IsReadOnly $True
This example makes partition Y read-only. Source: Microsoft, CC BY 4.0; transcript prompt/output removed. This example was not executed.