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

Protect your Android, iPhone, Mac, and Windows devices from threats by installing Microsoft Defender. Download Microsoft Defender on your devices either by:

Training: Get started with SharePoint in Microsoft 365. At office.com, sign in to SharePoint, then select the SharePoint tile.

Copilot in Word ushers in a new era of writing, leveraging the power of AI. Check out this article to learn more.

如何将 IF 函数 (与 Excel 中) AND、OR 和 NOT 函数结合使用，以在给定值之间进行逻辑比较。

Learn how to activate Windows using a product key or digital license, check your activation status, and link your Microsoft account.

Learn how to locate and manage your app permissions on Windows devices. Some apps or games need specific permissions to work properly.

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.

Update Surface devices and Windows. Download the latest drivers and firmware updates to keep your Surface devices performing their best.

Find out how to boot into safe mode in Windows from Settings, the sign-in screen, and a black or blank screen.