---
title: Lock
slug: device-management-apple/lock
createdAt: 2026-10-06T07:47:34.951Z
---

Locking a device forces the user to enter a password to access the device and prevents the user from reversing this restriction. The user is informed of this action via email. If the user has set a password for the device, then that password must be entered.

This feature is supported on macOS devices.

**Procedure **

1. Go to <font color="#323232">Device &amp; Users </font>> <font color="#323232">Devices</font>.
2. Select the check box for the device.
3. Select <font color="#323232">Lock</font> from the <font color="#323232">Actions</font> menu.

The <font color="#323232">Lock </font>dialogue for an iOS device displays additional options for you to enter a contact number and a message. The Lock Message field allows you enter up to 500 characters. The contact number and the message appear on the screen for the device you locked. The device user can call the number displayed on the locked device.

## Retry handling for NotNow responses on Apple devices

When a passcode-enabled device running iOS 26.0 or macOS 26.0 is locked, it may not be able to process certain MDM commands and may return a NotNow response. In some cases, if the device acknowledges another command in the same check-in flow, the earlier deferred command might remain pending even after the device is unlocked.

To address this, the server now identifies commands that received a NotNow response and retries them before ending communication with the device. This helps ensure that pending commands are retrieved after the device is unlocked.