An upgrade moves your PC from a previous version of Windows—such as Windows 7 or Windows 8.1—to Windows 10. An upgrade can take place on your existing device, though Microsoft recommends using Windows 10 on a new PC to take advantage of the latest features and security improvements.

Info for Windows Insiders. If you’re an Insider and the current preview build isn’t working for you, select Start > Settings > System > Recovery .Next to Go back , select Go back.This won’t remove your personal files, but it’ll remove recently installed apps and drivers, and change settings back to their defaults.

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Export contacts out of other email services. Export iCloud contacts. Export Gmail contacts – See Gmail help. Export Yahoo contacts – See Yahoo import and export help. Export Thunderbird contacts – See Mozilla support.

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。

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Select the temporary files, unused files, files synced to the cloud, or unused apps you want to remove, then select the Clean up button for each section.

重要: 在选择从媒体启动之前，应验证设备是否满足最低系统要求，因为满足后才允许安装 Windows 11，如果你至少具有 TPM 1.2（而不是最低系统要求的 TPM 2.0），它将不会根据处理器的系列和模型验证处理器是否在批准的 CPU 列表上。

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