Tip: If you're a Microsoft 365 Family or Personal subscriber you get Microsoft Defender, our advanced security software for Windows, Mac, iOS, and Android, as part of your subscription.Learn more at Getting started with Microsoft Defender.

Note: If you start to play a DVD or VCD in the Player Library, the Player automatically switches to Now Playing mode. The Blu-ray Disc format is not supported in Windows Media Player. To play a Blu-ray Disc, you need to use a non-Microsoft program that supports Blu-ray playback and a device capable of reading Blu-ray Discs.

Important: If your device is out of support, it is no longer receiving security updates from Microsoft and may become more vulnerable to security risks and viruses.For this reason, we strongly recommend that you update to the latest version of Windows. Each version of Windows is supported for 18 months.

You can easily insert a check mark (also known as a "tick mark") in Word, Outlook, Excel, or PowerPoint. These marks are static symbols. If you're looking for an interactive check box that you can click to check or uncheck, see: Add a check box or option button (Excel) or Make a checklist in Word. In your file, place the cursor where you want to insert the symbol.

When you need to protect the privacy of an email message, encrypt it. Encrypting an email message in Outlook means it's converted from readable plain text into scrambled cipher text.

如何激活预安装在新 Windows 10 计算机上的 Office 或使用新的产品密钥。

Important Because changing your Microsoft account password is slightly different than resetting a forgotten password, this page does not cover the steps to reset your account password.

Learn how to connect to a projector or to another PC in Windows using the keyboard shortcut "Windows logo key + P", the Connect app (for Windows 10), or the Wireless Display app (for Windows 11).

There are two types of rules in Outlook—server-based and client-only. Server-based rules When you're using a Microsoft Exchange Server account, some rules are server-based.These rules run on your mailbox on the Exchange mail server even when Outlook isn’t running.

检查你的版本. DirectX 是许多 Windows 游戏都需要的一种多媒体技术套件。 如果你的电脑未安装正确版本的 DirectX（产品包装盒上应标有所需的版本），游戏可能无法正常运行。