Learn how to use a USB flash drive or DVD to install or reinstall Windows 10, 8.1, 7, or 11. Find the software download website, product key, and recovery options.

Learn how to reinstall Windows 11 using installation media, such as a USB drive, SD card, or external hard drive. Compare different options and requirements for resetting, reinstalling, or cleaning your PC.

Learn how to locate your 48-digit BitLocker recovery key when you need to unlock an encrypted drive in Windows. The key can be attached to your Microsoft account, work or school account, printout, or USB flash drive.

Learn how to download and install or reinstall Office 2019, Office 2016, or Office 2013 on your PC or Mac. Find out how to activate Microsoft 365, troubleshoot issues, and customize your installation options.

Learn how to download and install Microsoft 365 or Office 2021 on your device, whether you have a Microsoft account, a work or school account, or a product key. Find out how to activate the apps, troubleshoot issues, and get support.

Learn how to mirror or project another device's screen to your Windows PC using Miracast. Follow the steps for Windows 11 or Windows 10 to install the Wireless Display app and connect to a TV, projector, or other display.

Learn how to use PC Health Check app to check your Windows device health, performance, and eligibility for Windows 11. Download and install the app from https://aka.ms/GetPCHealthCheckApp.

如果这是你第一次安装 Microsoft 365，则可能需要先执行一些设置步骤。展开下面的 “了解详细信息”部分。 但是如果是重新安装 Microsoft 365，且已兑换了产品密钥并拥有与 Microsoft 365 相关联的帐户，请转到“登录并安装 Office”的部分。

Learn how to protect yourself from the data breach of National Public Data, an online background check and fraud prevention service. Find out what data was exposed, the risks involved, and the actions to take with Microsoft Defender for Individuals.

了解如何接收从 Microsoft 购买的商品的退款或换货。