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条件是否不 (NOT) 符合你的条件，这时该怎么做呢？这三个函数均可以单独使用，但它们更常见于与 IF 函数成对使用。

Important: Before trying any of the solutions below, make sure you back up your personal files. You can back up your Windows PC, or insert a USB drive and use File Explorer to drag and copy important files to the USB drive.If you’re signing into Windows with a Microsoft account, your system settings will be automatically restored after updating, once you’re connected to the internet.

请确保已使用你的 Microsoft 帐户登录以购买 Windows 11 专业版 确认购买后，系统将提示你安装 Windows 11 专业版并重启电脑。 然后，你将运行 Windows 11 专业版。

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.

1. Sign in with your Microsoft account. You will be prompted to Sign in with Microsoft account. If you have an existing Microsoft account on your mobile device then you will be asked to confirm your account, then click Continue.. If you don't have an existing Microsoft account on your mobile device then you will be asked to sign into your account or create a new one, then click Continue.

In Windows 11, it is essential that you link your Microsoft account with the Windows 11 digital license on your device. Linking your Microsoft account with your digital license allows you to reactivate Windows using the Activation troubleshooter whenever you make a significant hardware change.

修复 Windows 中的声音或音频问题; 设置 Microsoft 新式无线耳机; 在 Microsoft Teams 中使用 Microsoft 新式无线耳机; 在 Microsoft Teams 中使用 Microsoft 新式 USB-C 耳机

The Access 365 Runtime is like previous runtimes in that all design-related UI is either removed or disabled. The Access 365 Runtime includes the Access Database Engine which contains a set of components that facilitate the transfer of data between existing Microsoft Office files such as Microsoft Office Access (*.mdb and *.accdb) files and Microsoft Office Excel (*.xls, *.xlsx, and *.xlsb ...

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.

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。