Press and hold (or right-click) the MP4 file you want to play, select Open with, and then choose your preferred file player from the list of applications.

在 Windows 8.1 或 Windows RT 8.1 中查找操作系统信息. 要查找设备运行的 Windows 版本，请按 Windows 徽标键 键 + R，并在“打开”框中键入“winver”，然后选择“确定”。. 如果你的设备运行的是 Windows 8.1 或 Windows RT 8.1，那么有关详细信息，可以参阅以下内容：

First time, infrequent senders, or senders marked [External] - While it's not unusual to receive an email or Teams message from someone for the first time, especially if they are outside your organization, this can be a sign of phishing.Slow down and take extra care at these times. When you get an email or a Teams message from somebody you don't recognize, or that Outlook or Teams identifies ...

If Windows Update finds an updated driver, it will download and install it, and your printer will automatically use it. If a device driver couldn’t be installed automatically, there may be an optional driver available that your printer can use.

To open File Explorer, select Windows logo key + E or go to Start and type File Explorer in the search box. Select File Explorer in the results.. Top topics. Here are answers to a few common questions about File Explorer: How can I open File Explorer and find the Windows 11 features?

这些步骤仅适用于 Office 专业增强版、Visio 专业版 或 Project Professional。 步骤 1：启动 Office 应用，例如 Word、Project 或 Visio，具体取决于你的购买。. 步骤 2：在“登录以设置 Office”窗口中，选择“我不想登录或创建帐户”（窗口底部的小型链接）。. 步骤 3：输入 Office 产品密钥，省略连字符。

To capture someone's attention in an email or meeting invite, type the @ symbol followed by their name within the message or invite. Doing so will highlight their name and prompt Outlook to add them to the To line, ensuring they notice, and add the @ symbol next to their message in the Inbox.

New to Xbox gaming on PC? Here's how to get started.

在快速設定中： 若要尋找藍牙的快速設定，請選取工作列右側的時間和日期旁 的 [網路]、[音效] 或 [電池] 圖示。 選取[藍牙] 將其開啟。如果在未連接任何藍牙裝置的情況下開啟此功能，它可能會顯示為[未連線] 。 如果您在快速設定中沒有看到藍牙 ，您可能需要新增它。

The Windows 10 free upgrade offer ended on July 29, 2016. To upgrade to Windows 10, you will need to have a compatible PC and purchase a full version of the software.We recommend that you don’t install Windows 10 on an older device, as some Windows 7 devices are not compatible with Windows 10 or could experience reduced feature availability.