Rules for modifying device properties

Many device properties have complex dependencies on other properties or device state. For example, the values of DEVPKEY_Device_Class and DEVPKEY_Device_ClassGuid must be consistent with one another.

Direct modification of reserved properties could invalidate device installation state. For example, if the DEVPKEY_Device_DeviceDesc is changed, system functionality (such as backup, driver rollback, and Windows Update) could break.

The following properties are read-only and can never be set with CM_Set_DevNode_Property or SetupDiSetDeviceProperty:

• DEVPKEY_Device_Address

• DEVPKEY_Device_BusNumber

• DEVPKEY_Device_BusTypeGuid

• DEVPKEY_Device_Capabilities

• DEVPKEY_Device_CompatibleIds

• DEVPKEY_Device_DevNodeStatus

• DEVPKEY_Device_EnumeratorName

• DEVPKEY_Device_HardwareIds

• DEVPKEY_Device_InstallState

• DEVPKEY_Device_InstanceId

• DEVPKEY_Device_LegacyBusType

• DEVPKEY_Device_LocationPaths

• DEVPKEY_Device_PDOName

• DEVPKEY_Device_PowerData

• DEVPKEY_Device_ProblemCode

• DEVPKEY_Device_RemovalPolicy

• DEVPKEY_Device_RemovalPolicyDefault

• DEVPKEY_Device_UINumber

• DEVPKEY_NAME

The following properties are writable. However, they are reserved for use by the operating system and must not be set directly:

• DEVPKEY_Device_Class

• DEVPKEY_Device_ClassGuid

• DEVPKEY_Device_DeviceDesc

• DEVPKEY_Device_Driver

• DEVPKEY_Device_DriverDesc

• DEVPKEY_Device_InstallDate

• DEVPKEY_Device_LowerFilters

• DEVPKEY_Device_Manufacturer

• DEVPKEY_Device_Service

• DEVPKEY_Device_UpperFilters

Note

Class installers and co-installers must not change device properties except for the friendly name (DEVPKEY_Device_FriendlyName). For more information, see Accessing Device Instance Properties.