“iTunes 无法连接到此 iPhone。尝试将禁用锁定(Lock)屏幕的 iPhone 连接到 PC 或Mac时，通常会出现“缺少值”错误。但其他各种原因——例如错误的硬件驱动程序和损坏的隐私设置——也可能导致它浮出水面。
尽管错误消息的性质很神秘，但按照下面的故障排除提示列表进行操作应该可以帮助您解决问题。前几节将重点介绍处理密码冻结的 iPhone。后续修复通常适用于所有 iPhone。
使用正确的密码解锁设备
您是否(Did)在 iPhone 上多次输入错误的锁屏密码？(Lock)如果是这样，设备可以冻结并显示“iPhone 已禁用”消息作为安全措施。这也可能导致 PC 或Mac(Mac)上的 iTunes 中出现“缺少值”错误，尤其是如果它是您以前从未将 iPhone 同步到的计算机。
等到(Wait)倒数计时器结束，然后再次重新输入正确的密码。如果您设法解锁 iPhone，您可能不会再遇到 iTunes 中的错误。
在恢复模式下恢复 iPhone
如果您不记得密码（或者如果您只看到没有倒数计时器的“iPhone 已禁用”消息），重新访问您的 iPhone 的唯一方法是将其恢复为出厂设置。
由于“值丢失”错误导致您无法访问 iOS 或将 iPhone 连接到 iTunes，因此执行重置的唯一方法是使用恢复模式(Recovery Mode)。
您确实需要 iTunes 才能进入恢复模式(Recovery Mode)，但它会强制程序连接到您的 iPhone，无论其状况如何。这是强制重启 iPhone 并进入恢复模式(force-restart your iPhone and enter Recovery Mode)的方法。
在恢复模式下，选择恢复 iPhone(Restore iPhone)选项。iTunes 应从Apple下载最新版本的 iOS，并使用该版本将您的 iPhone 恢复为默认设置。
如果您有Finder/iTunes backup of your iPhone，您可以在重置过程后使用它来恢复您的数据。否则，除了与 iCloud 同步的任何数据(data that syncs with iCloud)（如照片、笔记、语音备忘录等）外，您将丢失所有内容。
更换端口和电缆
将 iPhone 连接到PC 或Mac上的不同(Mac)USB端口可以帮助解决“iTunes 无法连接到此 iPhone”的任何随机实例。缺少值”错误。现在尝试这样做。
外部USB集线器也会导致连接问题，因此最好将电缆直接插入 PC 或Mac。此外，您可以通过仅连接 iPhone来消除来自其他USB设备的干扰。
电缆故障是导致 iTunes 错误的另一个原因。如果可能，请切换到其他 Lightning 电源线或MFi 认证的第三方线缆(MFi-certified third-party cable)。
重启 iPhone 和 PC/Mac
如果问题仍然存在，请重新启动您的 iPhone 和PC/Mac，然后重试。这应该有助于解决阻止设备相互通信的常见错误和其他异常情况。
要重新启动 iPhone，请前往Settings > General并选择Shut Down。向右滑动电源(Power )图标，等待 30 秒，然后按住侧边(Side )按钮，直到看到Apple标志。
(Run)在Windows中以(Windows)管理员身份(Administrator)运行iTunes
如果您在 PC 上使用 iTunes，以管理员身份运行该程序可能会允许它覆盖Windows中导致“缺少值”错误的任何与权限相关的问题。为此，请在“开始”菜单中键入(Start )iTunes ，然后选择“以管理员身份运行”(Run as administrator)。
如果您在桌面上看到 iTunes 图标，您还可以使用右键单击上下文菜单(right-click context menu)以提升的权限启动应用程序。
更新 iTunes
过时的 iTunes 版本可能存在导致“缺少值”错误的错误和问题。在您的 PC 或Mac上更新它会有所作为。
在 PC 上更新 iTunes (Update iTunes on PC )
打开 iTunes。然后，打开“帮助(Help )”菜单，选择“检查更新(Check for Updates)”，然后安装所有待处理的更新。如果您使用 iTunes 的Microsoft Store版本，则可以通过转到 Microsoft Store 的下载和更新(Downloads and updates)部分来更新程序。
在 Mac 上更新 iTunes(Update iTunes on Mac)
打开Mac App Store，切换到更新选项卡，然后应用(Updates )软件更新(Software Update)下的任何 iTunes更新。
禁用防病毒软件
第三方防病毒实用程序是 iPhone 上“缺少值”错误的另一个潜在原因。如果您在 PC 或Mac上运行了一个，请暂时禁用它并检查是否有帮助。
更新 iOS
你最近更新了 iOS 吗？运行过时版本的 iPhone 系统软件可能会导致 iPhone 上出现各种问题。最好将其更新到最新版本。为此，请转到“设置”(Settings) > “常规(General)” > “软件更新”(Software Update)，然后选择“下载并安装(Download and Install)” 。
(Reinstall Apple Mobile USB Driver)在Windows中(Windows)重新安装 Apple Mobile USB 驱动程序
如果您在 PC 上使用 iTunes，则应重新安装Apple Mobile USB 驱动程序(Apple Mobile USB Driver)。这应该有助于排除任何驱动程序损坏问题。
根据您使用的是标准版还是Microsoft Store版 iTunes，该过程会有所不同。
iTunes – 标准桌面版(iTunes – Standard Desktop Version)
1. 通过USB将 iPhone 连接到您的 PC 。然后，解锁你的 iPhone。
2. 按Windows + R打开运行(Run )框。
3. 输入以下文件路径并选择OK：
%ProgramFiles%\Common Files\Apple\Mobile Device Support\Drivers
4. 右键单击标记为usbaapl64.inf或usbaapl.inf的文件并选择安装(Install)。
5. 断开 iPhone 并重新启动计算机。
iTunes – 微软商店版本(iTunes – Microsoft Store Version)
1. 通过USB将 iPhone 连接到您的 PC 。然后，解锁你的 iPhone。
2. 按Windows + X并选择设备管理器(Device Manager)。
3. 展开便携式设备(Portable Devices)。
4. 右键单击 Apple iPhone并选择卸载设备(Uninstall device)。
5. 退出设备管理器(Device Manager)并重新启动计算机。
在 Windows 中安装硬件驱动程序
在Windows(Windows)中应用最新的硬件更新也应该有助于解决与 iTunes 相关的驱动程序问题。
1. 打开开始(Start )菜单并选择设置(Settings)。
2. 选择更新和安全(Update & Security)。
3. 选择检查更新(Check for updates)以扫描新的 Windows 更新。
4. 选择查看所有可选更新(View all optional updates)。
5. 选择并安装挂起的硬件驱动程序更新。
当您使用它时，您还应该考虑应用任何操作系统更新。
升级到 macOS Catalina 或更高版本
在Mac上，升级到 macOS 10.15 Catalina或更高版本意味着您将使用 Finder 与 iPhone 进行交互(use Finder to interact with your iPhone)。访问Mac App Store上的(App Store)更新(Updates )选项卡以执行升级。如果您使用 macOS 10.14 Mojave，请转至系统偏好设置(System Preferences )>软件更新(Software Update )。
重置隐私设置
iPhone 上损坏(Corrupt)的隐私设置可能会干扰并阻止它与 iTunes 通信。前往“设置”(Settings ) > “通用(General )” > “重置(Reset )” ，然后选择“重置位置和隐私(Reset Location & Privacy)”以重置 iPhone 的隐私设置。
如果您之前“信任”过您的 PC 或 Mac，则在重置过程后将 iPhone 重新连接到您的 PC 或Mac时，您必须再次点击(Mac)信任。(Trust)
重置所有设置
如果您仍然在 iTunes 中遇到相同的错误消息，您应该重置 iPhone 上的所有设置。转到设置(Settings )>常规(General )>重置(Reset )，然后选择重置所有设置(Reset All Settings)。
这应该可以解决阻止 iPhone 和PC/Mac相互通信的任何错误配置。
iTunes：找到的价值
上述修复很可能帮助您修复了“iTunes 无法连接到此 iPhone。iPhone 上的“值缺失”错误。如果冻结的锁定(Lock)屏幕是问题背后的原因，请尝试设置一个您可以记住的密码，以避免再次遇到此问题。如果没有，让您的 iPhone 和 iTunes 保持最新应该有助于最大限度地减少未来再次发生类似错误。
How to Fix “iTunes Could Not Connect to this iPhone. The Value is Missing” Error
The “iTunes could not connect to this iPhone. The value is missing” error mostly shows up when attempting tо connect a Lock ѕcreen-disabled iPhone to a PС or Maс. But various оther reasons—such as faultу hardware drivers and corrυpt privacy settings—can also caυse it to surface.
Despite the cryptic nature of the error message, working your way through the list of troubleshooting tips below should help you sort things out. The first couple of sections will focus on dealing with a passcode-frozen iPhone. Subsequent fixes apply to all iPhones in general.
Unlock Device With Correct Passcode
Did you enter the Lock screen passcode incorrectly multiple times on your iPhone? If so, the device can freeze and display an “iPhone is disabled” message as a security measure. That can also result in a “The value is missing” error in iTunes on the PC or Mac, especially if it’s a computer that you’ve never synced your iPhone to before.
Wait until the countdown timer ends and re-enter the correct passcode again. If you manage to unlock the iPhone, you may not come across the error in iTunes anymore.
Restore iPhone in Recovery Mode
If you can’t remember the passcode (or if you only see an ‘”iPhone is disabled” message without a countdown timer), the only way to regain access to your iPhone is to restore it to factory settings.
Since you can’t access iOS or connect your iPhone to iTunes due to “The value is missing” error, the only way to perform the reset is to use Recovery Mode.
You do need iTunes to enter Recovery Mode, but it forces the program to connect to your iPhone regardless of its condition. Here’s how to force-restart your iPhone and enter Recovery Mode.
In Recovery Mode, select the Restore iPhone option. iTunes shall download the latest version of iOS from Apple and use that to to restore your iPhone to its defaults.
If you have an iCloud or a Finder/iTunes backup of your iPhone, you can use that to restore your data after the reset procedure. If not, you lose everything except for any data that syncs with iCloud (such as photos, notes, voice memos, etc.).
Change Ports and Cable
Connecting your iPhone to a different USB port on your PC or Mac can help resolve any random instances of the “iTunes could not connect to this iPhone. The value is missing” error. Try doing that now.
External USB hubs also cause connectivity issues, so it’s a good idea to plug the cable directly into the PC or Mac. Additionally, you can eliminate interference from other USB devices by connecting your iPhone only.
A faulty cable is another reason that can result in iTunes errors. Switch to a different Lightning power cord or an MFi-certified third-party cable, if possible.
Restart iPhone and PC/Mac
If the issue persists, restart your iPhone and PC/Mac and try again. That should help resolve common bugs and other anomalies preventing the devices from communicating with each other.
To restart an iPhone, head over to Settings > General and select Shut Down. Swipe the Power icon to the right, wait for 30 seconds, and press and hold the Side button until you see the Apple logo.
Run iTunes as Administrator in Windows
If you use iTunes on the PC, running the program as an administrator could allow it to override any permission-related issues in Windows that result in “The value is missing” error. To do that, type itunes into the Start menu and select Run as administrator.
If you see an iTunes icon on the desktop, you can also use the right-click context menu to launch the application with elevated privileges.
Update iTunes
An outdated version of iTunes can have bugs and issues that result in “The value is missing” error. Updating it on your PC or Mac can make a difference.
Update iTunes on PC
Open iTunes. Then, open the Help menu, select Check for Updates, and install any pending updates. If you use the Microsoft Store version of iTunes, you can update the program by heading over to the Downloads and updates section of the Microsoft Store.
Update iTunes on Mac
Open the Mac App Store, switch to the Updates tab, and apply any iTunes updates under Software Update.
Disable Antivirus Software
Third-party antivirus utilities are another potential cause of the “The value is missing” error on the iPhone. If you have one running on your PC or Mac, disable it temporarily and check if that helps.
Update iOS
Have you updated iOS recently? Running a dated version of the iPhone’s system software can cause all sorts of issues to crop up on your iPhone. It’s best to update it to its latest version. To do that, go to Settings > General > Software Update and select Download and Install.
Reinstall Apple Mobile USB Driver in Windows
If you use iTunes on the PC, you should reinstall the Apple Mobile USB Driver. That should help rule out any driver corruption issues.
The procedure changes depending on whether you use the standard or the Microsoft Store version of iTunes.
iTunes – Standard Desktop Version
1. Connect the iPhone to your PC via USB. Then, unlock your iPhone.
2. Press Windows+R to open the Run box.
3. Enter the following file path and select OK:
%ProgramFiles%\Common Files\Apple\Mobile Device Support\Drivers
4. Right-click the file labeled usbaapl64.inf or usbaapl.inf and select Install.
5. Disconnect the iPhone and restart your computer.
iTunes – Microsoft Store Version
1. Connect the iPhone to your PC via USB. Then, unlock your iPhone.
2. Press Windows+X and select Device Manager.
3. Expand Portable Devices.
4. Right-click Apple iPhone and select Uninstall device.
5. Exit the Device Manager and restart your computer.
Install Hardware Drivers in Windows
Applying the latest hardware updates in Windows should also help resolve driver issues related to iTunes.
1. Open the Start menu and select Settings.
2. Select Update & Security.
3. Select Check for updates to scan for new Windows updates.
4. Select View all optional updates.
5. Select and install pending hardware driver updates.
While you’re at it, you should also consider applying any operating system updates.
Upgrade to macOS Catalina or Later
On the Mac, making the upgrade to macOS 10.15 Catalina or later means that you’ll use Finder to interact with your iPhone. Visit the Updates tab on the Mac’s App Store to perform the upgrade. If you use macOS 10.14 Mojave, go to System Preferences > Software Update instead.
Reset Privacy Settings
Corrupt privacy settings on the iPhone can interfere and prevent it from communicating with iTunes. Go to Settings > General > Reset and select Reset Location & Privacy to reset the iPhone’s privacy settings.
If you’ve previously “trusted” your PC or Mac, you must tap Trust again while reconnecting the iPhone to your PC or Mac after the reset procedure.
Reset All Settings
If you still keep running into the same error message in iTunes, you should reset all settings on the iPhone. Go to Settings > General > Reset and select Reset All Settings.
That should resolve any incorrect configurations preventing the iPhone and PC/Mac from communicating with each other.
iTunes: Value Found
The fixes above most likely helped you fix the “iTunes could not connect to this iPhone. The value is missing” error on the iPhone. If a frozen Lock screen was the reason behind the issue, try setting up a passcode that you can remember to avoid running into this problem again. If not, keeping your iPhone and iTunes up-to-date should help minimize similar errors from recurring in the future.
