SUM function - Microsoft Support
How to use the SUM function in Excel to add individual values, cell references, ranges, or a mix of all three.
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
下载适用于 Surface 的驱动程序和固件 - Microsoft 支持
更新 Surface 设备和 Windows。 下载最新的驱动程序和固件更新，以使 Surface 设备保持最佳性能。
Block senders or mark email as junk in Outlook.com or Outlook on the ...
Learn how to mark email as junk or block senders in Outlook.com or Outlook on the web.
Applies To:
Outlook on the web, Outlook.com
Add or invite people outside your org to a chat in Microsoft Teams
With External Access for Teams, you can add or invite anyone outside of your Teams org who uses Teams, Teams for personal use, Skype (for consumers), and Skype for Business to a one-to-one chat.
Applies To:
Microsoft Teams
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
Help in File Explorer - Microsoft Support
Learn how to open, navigate, and troubleshoot File Explorer in Windows, with answers to common questions and support assistance.
Share SharePoint files or folders - Microsoft Support
The files you store on a SharePoint site are usually available to everyone with permissions to the site, but you may want to share specific files or folders with people who don't otherwise have access to the site.
Applies To:
SharePoint Server Subscription Edition, SharePoint Server 2019, SharePoint in Microsoft 365, Office for business, Office 365 Small Business, Microsoft 365 admin, Office 365 operated by 21Vianet, Office 365 operated by 21Vianet - Small Business Admin, Office 365 operated by 21Vianet - Admin, SharePoint in Microsoft 365 Small Business, SharePoint operated by 21Vianet
Renew Microsoft 365 for personal or family use
Learn how to renew your Microsoft 365 Family or Microsoft 365 Personal subscription online or from a retail store.
Applies To:
Excel for Microsoft 365, Word for Microsoft 365, PowerPoint for Microsoft 365, Excel for Microsoft 365 for Mac, Word for Microsoft 365 for Mac, PowerPoint for Microsoft 365 for Mac, Microsoft 365 for home, Office for business, Office activation
Use voting buttons in messages - Microsoft Support
Add voting buttons to a message so that recipients can vote; results are tracked automatically in Outlook.
Applies To:
Outlook for Microsoft 365, Outlook 2021, Outlook 2019, Outlook 2016, Outlook 2013
Import contacts to Outlook for Windows - Microsoft Support
You import contacts to Outlook from other email providers using the Outlook Import/Export wizard. Import a csv file, Excel spreadsheet, vCard.
Applies To:
Outlook for Microsoft 365, Outlook 2021, Outlook 2019, Outlook 2016, Outlook 2013, Microsoft 365 admin, New Outlook for Windows