Find your Windows product key - Microsoft Support
Learn how to find a Windows product key for activation, and when you'll use a digital license instead.
Applies To:
Microsoft account dashboard
Which version of Windows operating system am I running?
Learn how to find which version of Windows operating system your PC is running and device specifications.
Recall an email message that you sent in Outlook
How to recall and/or replace an email message you sent by using Microsoft 365 and your built-in Exchange Server account.
Applies To:
Outlook for Microsoft 365, Outlook 2021, Outlook 2019, Outlook 2016, Microsoft 365 admin, Outlook on the web, Outlook.com, New Outlook for Windows
Add and request read receipts and delivery notifications in Outlook
How to add and request read receipts and delivery notifications in Outlook.
Applies To:
Outlook for Microsoft 365, Outlook 2021, Outlook 2019, Outlook 2016, Outlook on the web, Outlook.com, New Outlook for Windows, Outlook on the web for Exchange Server 2016, Outlook on the web for Exchange Server 2019
Create a drop-down list - Microsoft Support
You can insert a drop-down list of valid entries (also called a drop-down menu or drop-down box) in Excel to make data entry easier, or to limit entries to certain items that you define.
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
下载并安装或重新安装 Office 2019、Office 2016 或 Office 2013
了解如何在电脑上安装 Office 2013 或 Office for Mac 2011。
Applies To:
Office 2019, Office 2016, Office 2016 for Mac, Office 2013
Recover and restore deleted items in Outlook - Microsoft Support
Learn how to recover deleted items, such as email, contacts, calendar appointments, and tasks in Outlook.
Applies To:
Outlook for Microsoft 365, Outlook 2021, Outlook 2019, Outlook 2016, Outlook on the web, Office 365 operated by 21Vianet, Outlook.com, New Outlook for Windows
Upgrade to Windows 10: FAQ - Microsoft Support
Learn how to upgrade your existing device to Windows 10 or buy a new PC. Get answers to common questions about upgrading to Windows 10.
Learn about Microsoft Rewards - Microsoft Support
Discover how to earn Microsoft Rewards points through various activities and redeem them for exciting rewards.
Applies To:
Microsoft account dashboard
Get to know Game Bar on Windows | Xbox Support
Find out how to use Game Bar to capture game play, chat with friends, track achievements, and more.