Note: Offers vary by country.Be sure to redeem your rewards points in the same region you signed up in. Do not use a VPN while trying to redeem points. When redeeming points, use a mobile or landline phone number for authentication and not a VoIP phone number.

Windows 8.1 Update and Windows RT 8.1 Update (also known as KB 2919355) include improvements that make your favorite apps and settings easier to find and use, provide more familiar mouse and keyboard options, and update security and performance.Here’s what you need to know about installing this important update. Check to see if it’s already installed

解决激活错误. 如果 Microsoft 365 无法激活，其最后会变为未授权，且 Microsoft 365 的所有编辑功能都会被禁用。 Microsoft 可能由于多种原因变为未授权。

Windows Security provides built-in security options to help protect your device from malicious software attacks. To access the features described below, tap the Windows Start button, type windows security, select it from the results, and then select Device security.

Find help and how-to articles for Windows operating systems. Get support for Windows and learn about installation, updates, privacy, security and more.

To activate using your digital license, you'll need to upgrade to Windows 11 Pro: Save your work and close any open apps.

Excel makes it easy to crunch numbers. With Excel, you can streamline data entry with AutoFill. Then, get chart recommendations based on your data, and create them with one click.

A team is a group of people gathered to get something big done in your organization. Sometimes it’s your whole organization.. Teams are made up of channels, which are the conversations you have with your teammates.Each channel is dedicated to a specific topic, department, or project. For example, the Mark 8 Project team has General, Design, Digital Assets Web, Go to Market Plan, and Research ...

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.

Select Notifications to expand it, and turn notifications, banners, and sounds on or off for some or all notification senders.