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。

Important: Before trying any of the solutions below, make sure you back up your personal files. You can back up your Windows PC, or insert a USB drive and use File Explorer to drag and copy important files to the USB drive.If you’re signing into Windows with a Microsoft account, your system settings will be automatically restored after updating, once you’re connected to the internet.

Under System , select Display .Your PC should automatically detect your monitors and show your desktop. If you don't see the monitors, select Multiple displays , then Detect.

但如果需要测试多个条件，例如我们假设所有条件都需要为 True 或 False (AND)，或只有一个条件需要为 True 或 False (OR)，或者如果想要检查某个条件是否不 (NOT) 符合你的条件，这时该怎么做呢？这三个函数均可以单独使用，但它们更常见于与 IF 函数成对使用。

Windows devices may get new functionality at different times as Microsoft delivers non-security updates, fixes, improvements, and enhancements via several servicing technologies—including controlled feature rollout (CFR).. Windows will let you know if you need to restart your device to complete an update, and you can choose a time that works best for you to complete that update.

Observação: A melhor e mais segura maneira de obter atualizações de driver no Windows é sempre por meio do Windows Update.Se você estiver tendo problemas com o Windows Update, verifique primeiro se algum dos links em Atualizar o Windows pode ajudá-lo.

On a Mac? See Check for Office for Mac updates automatically.. Click here for the Latest updates for versions of Office that use Windows Installer (MSI).. Choose your version of Office. If you're not sure what version of Office you have, see What version of Office am I using?. Not sure which type of install you have?

你可以使用安装介质（U 盘或 DVD）来安装 Windows 的新副本、执行全新安装或重新安装 Windows。 要创建安装介质，请转到软件下载网站，你可以在这里找到分步说明。 在该网站上，你可以选择 Windows 版本，并使用 U 盘或 DVD 创建自己的安装介质。

如果可以登录，但 Outlook.com 出现问题，请检查服务状态。 如果状态不是绿色，请等到服务正常运行再重试。 Microsoft 始终保持留意异常的登录活动，以防其他人试图登录到你的帐户。 如果你正在新的地方旅行或使用新设备，我们可能会要求你确认是否真是你本人。

If you're running Windows 8.1 or earlier, or if your PC doesn't meet the minimum system requirements to run Windows 11, consider moving to a new Windows 11 device. Find a PC that meets your needs. Set up your Microsoft account to transfer files and favorites. One account connects your device across Microsoft apps and services like Microsoft 365, OneDrive, Edge, and Microsoft Store.