您是否发现某些事件或约会没有显示在 iPhone 的日历上？或者，您的 iPhone 没有将新事件同步到其他 iCloud 设备？在本文中，我们将解释为什么会发生这种情况以及如何解决问题。
iCloud日历(Calendar)可能由于多种原因无法同步事件，包括互联网连接不良、日期和时间设置错误、同步设置错误、软件错误等。当您的 iPhone 日历无法在您的设备之间同步事件时，我们列出了 11 种尝试。
首先，请确认您已登录正确的Apple ID帐户。前往“设置”(Settings)，轻点屏幕顶部的姓名，并确保Apple ID帐户是您的。如果不是，请滚动到页面底部，点击退出(Sign Out)，然后登录到正确的帐户。
1.启用日历同步
首先，确保您的 iPhone 配置为与连接到您帐户的其他设备共享和接收日历数据。为此，请转到“设置”(Settings ) > “日历( Calendar )” > “帐户( Accounts)” ，然后选择受影响的帐户。
对于 iCloud 日历，在 Accounts 页面上选择iCloud ，然后在出现的(iCloud)Apple ID页面上再次点击iCloud 。
在使用 iCloud 的应用(Apps Using iCloud)部分中，确保日历(Calendars)已打开。
要修复第三方日历（例如Google 日历）上的同步问题，请在“(Google Calendar)帐户(Accounts)”页面上选择第三方服务。
接下来，确保日历(Calendars)已打开。
重新启动日历同步可能会解决您的 iPhone 日历不同步的问题，因此请关闭“日历(Calendars)”选项并将其重新打开。
2.检查互联网连接
如果在您的帐户上启用日历同步后，日历(Calendar)应用程序未显示更新的事件，请检查您的互联网是否正常工作。启动浏览器并检查它是否加载网页。如果您使用蜂窝数据，您需要确保日历(Calendar)可以访问您的移动数据。
转到设置(Settings )>移动数据( Mobile Data)（或蜂窝数据(Cellular Data)），滚动浏览列表中的应用程序并确保日历(Calendar)已打开。
您还可以打开飞行模式(airplane mode)并将其关闭。这将刷新你的 iPhone 的连接，并希望让一切恢复正常。
对于Wi-Fi连接，重启路由器并重新加入网络。仍然无法访问互联网？尝试将路由器重置(resetting the router)为出厂默认设置。我们还在本 Wi-Fi 故障排除指南(this Wi-Fi troubleshooting guide)中汇编了一些连接问题的潜在解决方案。
3.禁用低数据模式
为了减少蜂窝网络和 Wi-Fi 的使用，iOS低数据(Low Data)模式会暂时暂停后台服务，例如自动应用更新、后台应用刷新(background app refresh)、应用同步等。如果 iCloud 日历未同步，请确保您的 iPhone 未处于低数据状态数据模式(Low Data Mode)。
转到设置(Settings)>移动数据(Mobile Data)（或蜂窝）>移动数据选项(Mobile Data Options)（或蜂窝数据选项(Cellular Data Options)并关闭低数据模式(Low Data Mode)。
4.禁用低功耗模式
低功耗模式(Low Power Mode)是 iOS 的另一项功能，可暂时禁用 iCloud 同步和其他后台服务，以减少电池消耗。如果您的 iPhone 始终处于低电量模式(Low Power Mode)，来自其他 iCloud 设备的日历事件将不会反映在您的 iPhone 日历上。关闭低功耗模式(Low Power Mode)并等待几分钟让Apple填充您的日历。
打开控制中心(Control Center)并点击黄色电池图标(yellow battery icon)以禁用低功耗模式。
如果此图标在“控制中心(Control Center)”中不可用，请转到“设置”(Settings ) > “电池( Battery)”并关闭“低功耗模式”(Low Power Mode)。
5. 刷新日历
(Apple)如果您的 iPhone（或 iPad）无法与其他设备同步事件，Apple建议刷新连接到日历应用程序的日历。(Calendar)为此，请启动日历(Calendar)应用程序并点击屏幕底部的日历。(Calendars)
在列表上向下滑动(Swipe)并在刷新图标弹出时松开。
点击完成(Done)并检查丢失的事件现在是否出现在您的日历上。
6. 检查日期和时间设置
如果 iPhone 的日期和时间不正确，iCloud 不会同步日历事件。转到设置(Settings )>常规( General )>日期和时间( Date & Time)，并确保自动设置(Set Automatically)选项已打开。
此外，确保您的 iPhone 使用位置数据来自动确定正确的日期、时间和时区设置。转到设置(Settings )>隐私( Privacy )>定位服务( Location Services )>系统服务(System Services)并确保启用设置时区(Setting Time Zone)。
7.更改同步时间范围(Synchronization Time Frame)
在 iPhone 日历上找不到旧活动？日历(Calendar)应用程序是否仅显示最近的事件？前往(Head)日历设置并更改同步时间范围以同步所有事件。
前往设置(Settings )>日历( Calendar )>同步( Sync)，然后选择所有事件(All Events)。
这将确保来自其他设备的所有事件（旧的和新的）同步到您的日历。
8.检查默认日历
iOS 允许您在 iPhone 上使用多个日历，但您必须选择一个作为默认日历帐户。iOS 将 iPhone 上创建的事件存储/同步到默认日历帐户。如果您 iPhone 上的事件在其他 iCloud 设备上丢失，请确保您的 iCloud 是默认日历帐户。
前往“设置”(Settings ) > “日历( Calendar )” > “默认日历(Default Calendar)”，然后在 iCloud 部分中选择其中一个日历。
9. 检查 iCloud 日历状态
如果 iCloud日历(Calendar)服务器出现故障，您的 iPhone 上的事件可能会丢失。访问Apple 系统状态页面(Apple System Status page)以确认 iCloud日历(Calendar)服务器是否在线并正常运行。
绿色指示灯表示 iCloud日历(Calendar)已启动并正在运行，而黄色指示灯表示服务中断或服务器出现问题。
10.重启iPhone
重新启动您的 iPhone 可以解决许多 iCloud 应用程序和服务上的同步问题(fix synchronization issues on many iCloud apps and services)。如果到目前为止所有故障排除技术都不起作用，请关闭您的 iPhone 并检查日历(Calendar)是否在重新启动时同步您的事件。如果问题仍然存在，请尝试重新启动连接到您的Apple ID帐户的其他 iCloud 设备。
11.重新添加日历
一些遇到类似问题(iPhone users who experienced similar issues)的 iPhone 用户可以通过删除并重新添加日历帐户来解决问题。前往“设置”(Settings ) > “日历( Calendar )” > “帐户( Accounts)” ，然后选择日历帐户。
对于第三方日历，轻点“删除帐户(Delete Account)”以从 iPhone 中删除日历。
返回“帐户(Accounts)”页面并点击“添加帐户(Add Account)”以重新添加日历。
您需要退出Apple ID才能从您的设备中删除 iCloud 日历。点击 iCloud 日历，然后点击退出(Sign Out)以继续。
注意：(Note:)在 iPhone 或 iPad 上退出Apple ID将使某些应用程序无法使用并从您的设备中删除某些文件（例如Apple Music下载）。我们建议您在退出Apple ID之前在本地（到Mac或 PC）(Mac)备份您的设备(backing up your device locally)。
不错过任何活动
这些是 iPhone 和 iPad 上 iCloud日历(Calendar)同步问题的可靠解决方案。如果问题仍然存在，请将您的设备更新到最新的 iOS 版本；如果您的设备已过时或充满错误，日历可能会出现故障。(Calendar)将设备的设置重置为出厂默认设置(Resetting your device’s settings to factory default)（设置(Settings )>常规( General )>重置( Reset )>重置所有设置( Reset All Settings)）也可以解决问题。
iPhone Calendar Not Syncing? 11 Ways To Fix
Do you find that some events or appointments aren’t shоwing up on yoυr іРhone’s calendar? Or perhaps, уour iPhone doesn’t sync new events to other iCloud devіces? In this artiсle, we’ll explain why that happens and how to resolve the problem.
iCloud Calendar may fail to synchronize events for many reasons, ranging from poor internet connectivity to incorrect date & time settings, wrong synchronization settings, software bugs, and so on. We’ve listed 11 things to try when your iPhone calendar won’t sync events across your devices.
Before anything, confirm that you’re signed in to the correct Apple ID account. Go to Settings, tap the name at the top of the screen, and make sure the Apple ID account is yours. If it isn’t, scroll to the bottom of the page, tap Sign Out, and sign in to the correct account.
1. Enable Calendar Synchronization
First, make sure your iPhone is configured to share and receive calendar data with other devices connected to your accounts. To do this, go to Settings > Calendar > Accounts and select the affected account.
For iCloud calendar, select iCloud on the Accounts page and tap iCloud again on the resulting Apple ID page.
In the Apps Using iCloud section, make sure Calendars is toggled on.
To fix synchronization issues on third-party calendars (Google Calendar, for example), select the third-party service on the Accounts page.
Next, make sure Calendars is toggled on.
Re-initiating calendar synchronization might fix the problem with your iPhone calendar not syncing, so toggle off the Calendars option and turn it back on.
2. Check Internet Connection
If the Calendar app doesn’t display updated events despite enabling calendar synchronization on your accounts, check that your internet is working correctly. Launch your browser and check if it loads webpages. If you’re using cellular data, you want to make sure Calendar has access to your mobile data.
Go to Settings > Mobile Data (or Cellular Data), scroll through the apps on the list and ensure Calendar is toggled on.
You can also turn on airplane mode and turn it back off. That’ll refresh your iPhone’s connection and hopefully set things back in order.
For Wi-Fi connection, power cycle the router and rejoin the network. Still don’t have internet access? Try resetting the router to factory default. We’ve also compiled some potential solutions to connectivity issues in this Wi-Fi troubleshooting guide.
3. Disable Low Data Mode
To reduce cellular and Wi-Fi usage, the iOS Low Data mode temporarily pauses background services like automatic app updates, background app refresh, app synchronization, etc. If the iCloud calendar isn’t syncing, make sure your iPhone isn’t on Low Data Mode.
Go to Settings > Mobile Data (or Cellular) > Mobile Data Options (or Cellular Data Options and toggle off Low Data Mode.
4. Disable Low Power Mode
Low Power Mode is another iOS feature that temporarily disables iCloud synchronization and other background services—to reduce battery consumption. If your iPhone is always on Low Power Mode, calendar events from other iCloud devices won’t reflect on your iPhone calendar. Turn off Low Power Mode and wait for some minutes for Apple to populate your calendar.
Open the Control Center and tap the yellow battery icon to disable Low Power Mode.
If this icon isn’t available in the Control Center, go to Settings > Battery and toggle off Low Power Mode.
5. Refresh Calendars
Apple recommends refreshing the calendars connected to the Calendar app if your iPhone (or iPad) won’t synchronize events with other devices. To do this, launch the Calendar app and tap Calendars at the bottom of the screen.
Swipe down on the list and release when the refresh icon pops up.
Tap Done and check if the missing events now appear on your calendar.
6. Check Date and Time Settings
iCloud won’t sync calendar events if your iPhone’s date and time are incorrect. Go to Settings > General > Date & Time and make sure the Set Automatically option is toggled on.
Additionally, ensure that your iPhone uses location data to automatically determine the correct date, time, and time zone settings. Go to Settings > Privacy > Location Services > System Services and ensure Setting Time Zone is enabled.
7. Change Synchronization Time Frame
Can’t find old events on your iPhone calendar? Does the Calendar app only display recent events? Head to the calendar settings and change the synchronization time frame to sync all events.
Go to Settings > Calendar > Sync and select All Events.
That’ll ensure that all events (old and new) from other devices sync to your calendar.
8. Check Default Calendar
iOS lets you use multiple calendars on your iPhone but you must choose one as the default calendar account. iOS stores/syncs events created on your iPhone to the default calendar account. If events on your iPhone are missing on other iCloud devices, make sure your iCloud is the default calendar account.
Go to Settings > Calendar > Default Calendar and select one of the calendars in the iCloud section.
9. Check iCloud Calendar Status
Events may go missing on your iPhone if the iCloud Calendar servers are down. Visit the Apple System Status page to confirm if the iCloud Calendar servers are online and operating normally.
A green indicator means iCloud Calendar is up and running while a yellow indicator signifies service outages or server problems.
10. Restart iPhone
Rebooting your iPhone can fix synchronization issues on many iCloud apps and services. If all troubleshooting techniques so far didn’t work, shut down your iPhone and check if Calendar syncs your events when it comes back on. If the problem persists, try restarting other iCloud devices connected to your Apple ID account.
11. Re-Add Calendar
Some iPhone users who experienced similar issues were able to resolve the problem by deleting and re-adding the calendar account. Go to Settings > Calendar > Accounts and select the calendar account.
For third-party calendars, tap Delete Account to remove the calendar from your iPhone.
Return to the Accounts page and tap Add Account to re-add the calendar.
You’ll need to sign out of Apple ID to remove an iCloud Calendar from your device. Tap the iCloud calendar and tap Sign Out to proceed.
Note: Signing out of Apple ID on iPhone or iPad will render some apps unusable and remove some files (e.g. Apple Music downloads) from your device. We recommend backing up your device locally (to a Mac or PC) before signing out of Apple ID.
Never Miss an Event
These are surefire solutions to iCloud Calendar synchronization issues on iPhone and iPad. Should the problem persist, update your device to the latest iOS version; Calendar may malfunction if your device is outdated or filled with bugs. Resetting your device’s settings to factory default (Settings > General > Reset > Reset All Settings) may also fix the problem.
