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Download and install or reinstall Microsoft 365 or Office 2021 on a PC ...
Change from a 32-bit version to a 64-bit version or vice versa. Activate Windows. Fix Bluetooth problems in Windows. Learn how to install, reinstall, or activate Microsoft 365 or Office 2019 on a PC or Mac.
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
Use the SUM function to sum numbers in a range - Microsoft Support
You can use a simple formula to sum numbers in a range (a group of cells), but the SUM function is easier to use when you’re working with more than a few numbers. For example =SUM (A2:A6) is less likely to have typing errors than =A2+A3+A4+A5+A6.
Applies To: Excel for Microsoft 365, Excel for the web, Excel 2021, Excel 2019, Excel 2016
Sign in to SharePoint - Microsoft Support
SharePoint is a browser-based app that you connect to through your web browser, like so: Go to office.com, and sign in to your work or school account. In the upper left corner of the window, select the app launcher > All apps > SharePoint.
Applies To: SharePoint in Microsoft 365
How to sign in to Hotmail - Microsoft Support
Hotmail is now Outlook.com. Learn how to sign in to access your Outlook.com, Hotmail, Live, or MSN email account.
Applies To: Outlook.com
Screen mirroring and projecting to your PC or wireless display
Cast to a display from a Windows PC. You can wirelessly connect your PC to a TV, projector, or other kind of external display that supports Miracast. Turn on your TV, projector, or other display. If you're using a Miracast dongle or adapter, make sure it's plugged in to the display.
在电脑或 Mac 上下载并安装或重新安装 Microsoft 365 或 Office 2021 - Microsoft 支持
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 ...
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
Fix sound or audio problems in Windows - Microsoft Support
1. Check your speaker output. 2. Run the audio troubleshooter. 3. Verify that all Windows Updates are installed. 4. Check your cables, plugs, jacks, volume, speaker, and headphone connections. 5. Check sound settings. 6. Fix your audio drivers. 7. Set your audio device as the default device. 8. Turn off audio enhancements. 9. Restart Audio Services
Uninstall or remove apps and programs in Windows
Uninstall from the Start menu. Select Start > All apps and search for the app in the list shown. Press and hold (or right-click) on the app, then select Uninstall. Uninstall in Settings. Select Start > Settings > Apps > Apps & features . Find the app you want to remove, select More > Uninstall.
Which version of Windows operating system am I running?
Find operating system info in Windows 11. To find out which version of Windows your device is running, press the Windows logo key + R, type winver in the Open box, and then select OK. Here’s how to learn more: Select Start > Settings > System > About . Open About settings.
Contact Us - Microsoft Support
Get help and support, whether you're shopping now or need help with a past purchase. Contact Microsoft Support. Find solutions to common problems, or get help from a support agent.