Certificate authority (CA) A certificate authority is an entity similar to a notary public.It issues digital certificates, signs certificates to verify their validity and tracks which certificates have been revoked or have expired.

Choose an option for the ribbon: Show Tabs and Commands keeps all the tabs and commands on the ribbon visible all the time.. Show tabs shows only the ribbon tabs, so you see more of your document, and you can still quickly switch among the tabs.. Auto-Hide ribbon hides the ribbon for the best view of your document, and only shows the ribbon when you select the ellipsis (...

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Microsoft added OAuth support for Yahoo! accounts in the Windows 10 Creators update. To install the Creators Update now, go to the software download site, and select Update now.For more information about Windows updates, see Get the latest Windows update.. If you have a Japanese Yahoo! email account, you'll need to do the following:

在 “个性化设置背景”旁边的列表中，选择“图片”、“ 纯色”、“ 幻灯片放映”或“ Windows 聚焦 (”，) 查看来自世界各地的新图像。

Get more out of your email with Outlook.com. We've streamlined search to make it easier than ever to find what you're looking for. New features like Files and attachment previews let you see your pictures and files without leaving your inbox.

Download and install the My Apps Secure Sign-in Extension. Download and install the My Apps Secure Sign-in Extension, if you're prompted. This extension helps you use your desktop browser to use single sign-on with your organization's cloud apps.

Press and hold (or right-click) the file or folder, select (or point to) Send to, and then select Compressed (zipped) folder. A new zipped folder with the same name is created in the same location.

Get productive quickly with Microsoft 365 videos and tutorials. Explore Microsoft 365 training guides and tips to collaborate with anyone, anywhere.

Find everything you need to manage your Xbox account, profile, and more.