了解如何使用产品密钥或数字许可证激活 Windows、检查激活状态，以及链接Microsoft 帐户。

Microsoft Defender is a security app that helps people and families stay safer online with malware protection, web protection, real-time security notifications, and security tips.Microsoft Defender is included in a Microsoft 365 Family or Personal subscription and works on your phone (Android or iOS), PC, and Mac.

注意: 如果使用 Microsoft 帐户 （例如 Outlook.com 、Hotmail、Live 或 MSN 电子邮件帐户）而不是工作或学校帐户登录，请注销，然后使用正确的帐户重新登录。 不确定使用哪个帐户登录？ 在 Outlook 导航标头中选择 “帐户管理员 ”。 如果未使用所需帐户登录，请选择“ 注销 ”并重新开始该过程，或选择 ...

Note: Some cameras won't appear in the Camera settings page.These include infrared (IR) cameras used for Windows Hello Face authentication, cameras using DirectShow technology (like many apps provided by DSLR or action camera manufacturers so their devices can be used as webcams), and proprietary cameras that aren't managed by Windows—such as industrial cameras and many networked cameras.

Microsoft support is here to help you with Microsoft products. Find how-to articles, videos, and training for Microsoft Copilot, Microsoft 365, Windows, Surface, and more.

Contact Microsoft Support. Find solutions to common problems, or get help from a support agent.

Test your camera with the Camera app. Select Start , then choose Camera from your apps. If you're asked to allow access to the Camera, select Yes.If the camera works in the Camera app, the problem might be with the app you're trying to use.

Select Start > Settings > Personalization.The preview window gives you a sneak peek of your changes as you make them. In Personalize your background, you can select a picture, a solid color, or a slideshow of pictures you create.Or you can choose Windows spotlight to see a new image from around the world every day.

To open the On-Screen Keyboard. Go to Start , then select Settings > Accessibility > Keyboard, and turn on the On-Screen Keyboard toggle. A keyboard that can be used to move around the screen and enter text will appear on the screen. The keyboard will remain on the screen until you close it.

Updates to the default screen and sleep settings now help you use energy more efficiently and extend battery life. You can find efficiency settings in Windows 11 at Settings > System > Power & battery.. For a guided walkthrough of how each of the power and battery settings can improve your device's performance, click the button to open the Get Help app: