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We’re continually releasing updates to our application, based on customer feedback. Check out What's New in the latest updates for Skype on desktop and mobile.

Efficiency mode What is efficiency mode in Microsoft Edge? Efficiency mode is designed to help extend battery life. It minimizes power usage by reducing resource usage through modifying background tab activity and some foreground activity, as well as putting inactive background tabs to sleep after 30 minutes or less of inactivity (if Save resources with sleeping tabs is on).

Tip: If you're a Microsoft 365 Family or Personal subscriber you get Microsoft Defender, our advanced security software for Windows, Mac, iOS, and Android, as part of your subscription.Learn more at Getting started with Microsoft Defender.

若要在 Outlook.com 中获取支持，请单击此处或选择菜单栏上的帮助，然后输入查询。 如果自助服务无法解决问题，请向下滚动到“仍需要帮助？”，然后选择“是”。 若要在 Outlook.com 中联系我们，需要登录。

Windows 10, version 2004 and Windows Server, version 2004 update history; End of service statement; December 14, 2021—KB5008212 (OS Builds 19041.1415, 19042.1415, 19043.1415, and 19044.1415)

Important: When you break a link to the source workbook of an workbook link, all formulas that use the value in the source workbook are converted to their current values.

Battery Life: Lowering your refresh rate can save battery power by reducing the amount of energy your display consumes.This can be useful when you are using a laptop or tablet and want to extend your battery life.

Important: Workbook links are considered potentially unsafe and must be enabled when you open a formula workbook.When you open a formula workbook, click Enable Content in the Message Bar to allow the workbook links to function. If you don't, Excel keeps the most recent values and disables refreshing the links with values from the data workbook.

Important: If your device is out of support, it is no longer receiving security updates from Microsoft and may become more vulnerable to security risks and viruses.Therefore, we strongly recommend that you update to the latest version of Windows. Each version of Windows is supported for 18 months.