Find your Office product key. Office 365 Office 2019 Office 2016 Office 2013. Many tasks for Office products don't require a product key because your Microsoft account takes care of them instead. Using product keys with Office.

Use the DATEDIF function when you want to calculate the difference between two dates. First put a start date in a cell, and an end date in another. Then type a formula like one of the following. Warning: If the Start_date is greater than the End_date, the result will be #NUM!.

若要检查更新，请选择“ 开始 > 设置 > Windows 更新 ”，然后选择“ 检查更新 ”。. 如果有可用的更新，可以选择安装它们。. 检查更新. 如果在更新设备时遇到问题（包括以前的主要更新出现问题），请参阅 排查更新 Windows 问题 中的常见修补程序。. 如果Windows ...

In the Settings app on your Windows device, select Accounts > Sign-in options or use the following shortcut: Sign-in options. Under Ways to sign in , you have three choices to sign in with Windows Hello: Select Facial recognition (Windows Hello) to set up facial recognition sign-in with your PC's infrared camera or an external infrared camera.

To sign out everywhere. Sign in to your Advanced security options on your Microsoft account security dashboard. Sign in. Scroll down to Sign me out and select Sign me out. Note: Sign out may take up to 24 hours.

Select Start , and then select Power > Hibernate. Press the Windows logo key + X on your keyboard, and then select Shut down or sign out > Hibernate. Note: If devices connected to your PC (like monitors, printers, or scanners) aren't working properly after waking up from sleep or hibernate, you might need to disconnect and reconnect your device ...

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Windows 10. To turn off your PC in Windows 10, select the Start button, select the Power button, and then select Shut down.

Change your background during a meeting. In your meeting controls, select More actions > Effects and avatars . Select Blur to blur your background, or choose from the available images to replace it. To upload an image of your own, select Add new and pick a .JPG, .PNG, or .BMP file from your computer. To turn off background effects, select None.

Create a print only list. Go to Home and select the down arrow next to the Bullets button. In the drop down menu, select Define New Bullet. Select Symbol and find a box character. If you don't initially see one, change Font to Wingdings or Segoe UI Symbol. Select OK twice, and create your list. How to create a checklist in Word that can be ...