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激活 Office - Microsoft 支持
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。
Applies To: Excel for Microsoft 365, Word for Microsoft 365, Outlook for Microsoft 365, PowerPoint for Microsoft 365, Access for Microsoft 365, OneNote for Microsoft 365, Publisher for Microsoft 365, Visio Plan 2, Excel 2021, Word 2021, Outlook 2021, PowerPoint 2021, Access 2021, Project Standard 2021, Publisher 2021, Visio Professional 2021, Visio Standard 2021, Office 2021, OneNote 2021, Excel 2019, Word 2019, Outlook 2019, PowerPoint 2019, Access 2019, Project Standard 2019, Publisher 2019, Visio Professional 2019, Visio Standard 2019, Office 2019, Excel 2016, Word 2016, Outlook 2016, PowerPoint 2016, Access 2016, OneNote 2016, Publisher 2016, Office 2016, Microsoft 365 for home, Office for business, Office.com, Project for Office 365
Manage app permissions for your camera in Windows
To use your camera with apps on Windows 11, you'll need to turn on some permissions in Camera settings. Then, you'll need to check your app permissions if you want to use your camera with apps.
SUMIFS function - Microsoft Support
How to use the SUMIFS function in Excel, one of Excel’s math and trig functions, to add arguments that meet multiple criteria.
Applies To: Excel for Microsoft 365, Excel for Microsoft 365 for Mac, Excel for the web, Excel 2021, Excel 2021 for Mac, Excel 2019, Excel 2019 for Mac, Excel 2016, Excel Web App
Set up your Microsoft 365 sign-in for multi-factor authentication
Learn how to set up your user account for multifactor authentication with Microsoft 365.
Applies To: Office for business, Microsoft 365 admin
Defragment your Windows 10 PC - Microsoft Support
Defragment your Windows 10 PC. Optimizing your drives can help your PC run smoother and boot up faster.
Turn on device encryption - Microsoft Support
Learn how to turn on device encryption, or standard BitLocker encryption in Windows.
如何登录 Outlook 网页版 - Microsoft 支持
Outlook 网页版是组织使用的基于 Web 的 Outlook 版本。你需要使用工作或学校帐户登录才能访问此基于 Web 的 Outlook 版本。 你的工作或学校帐户通常由组织中的某人分配给你。
Applies To: Office for business, Office 365 Small Business, Outlook on the web, Outlook on the web for Exchange Server 2016
Where are my contacts in Windows 10? - Microsoft Support
Learn how to filter the contacts in the People app on your Windows 10 PC so you can see all of your Skype contacts.
在电脑或 Mac 上下载并安装或重新安装 Microsoft 365 或 Office 2021 - Microsoft 支持
准备好安装了吗? 在开始之前,请确保电脑或 Mac 满足 系统要求。. 如果你已兑换产品密钥,只需重新安装应用,或者知道你已通过工作或学校分配了许可证,则可以跳到登录部分 ,下载并安装 Microsoft 365 或 Office。 但是,如果是 首次 安装 Microsoft 365 或 Office,可能需要先执行一些步骤。
Applies To: Office 2021, Office 2021 for Mac, Office 2019, Office 2019 for Mac, Microsoft 365 for home, Office for business, Office 365 Small Business, Microsoft 365 admin, Office 365 operated by 21Vianet, Office 365 operated by 21Vianet - Admin, Microsoft 365 for Mac, Office 365 Germany - Enterprise, Office 365 Germany - Enterprise admin, Office.com
在 Windows 中以安全模式启动电脑 - Microsoft 支持
了解如何从“设置”、登录屏幕和黑屏或空白屏幕启动到 Windows 中的安全模式。