Give your PC a Fresh Start. Resetting your PC lets you perform a clean reinstallation and update of Windows while keeping your personal data and most Windows settings intact. In some cases, a clean installation may improve your device's performance, security, browsing experience, and battery life.

You can use a simple formula to sum numbers in a range (a group of cells), but the SUM function is easier to use when you’re working with more than a few numbers. For example =SUM (A2:A6) is less likely to have typing errors than =A2+A3+A4+A5+A6.

在 Excel 中，IF 函数允许通过测试某个条件并返回结果（如果该条件为 True 或 False），在值和预期值之间进行逻辑比较。. 但如果需要测试多个条件，例如我们假设所有条件都需要为 True 或 False (AND)，或只有一个条件需要为 True 或 False (OR)，或者如果想要检查某个 ...

How to make PC games work better. Troubleshoot game audio or video issues on Windows. Troubleshoot gameplay, performance, and stability issues on a Windows device. How to get software and driver updates for Windows devices. Optimize available storage by customizing game installations.

When you’re running a game, Game Mode: Prevents Windows Update from performing driver installations and sending restart notifications. Helps achieve a more stable frame rate depending on the specific game and system. To turn Game Mode on or off: Press the Start button , type Settings in the search box, and then select Settings.

After you upgrade to Windows 10, you can reinstall or do a clean installation on the same device. You won't need a product key to reactivate Windows 10 on the same hardware. For more info on how to create your own Windows 10 installation media, see the Microsoft software download website.

从 Microsoft 获取免费的 Windows 主题，以个性化设置电脑的背景、颜色和声音。.

当你与邮件服务器的连接中断时，例如，当你乘坐的飞机上没有 WiFi 或 Internet 连接断开时，你仍然可以访问之前下载的所有电子邮件、日历数据、联系人和任务。 可以阅读和撰写邮件、创建约会以及添加联系人。

您可以将同一行或列中的两个或多个单元格合并为一个单元格。. 例如，您可以水平合并多个单元格，以创建横跨多个列的表格标题。. 选择要合并的单元格。. 注意: 如果表格中的单元格没有可见的边框，您可能会发现显示网格线很有帮助。. 单击“ 表格工具 ...

Windows 更新疑难解答. 如果你在下载和安装 Windows 更新时收到错误代码，更新疑难解答可以帮助解决该问题。. 选择“ 开始 ”>“ 设置 ”>“ 系统 ”>“ 疑难解答 ”>“ 其他疑难解答 ”。. 接下来，在 最常用的 下，选择 Windows 更新 > 运行。. 运行完疑难解答后 ...