Time Machine提供了一种非常方便的方式来保护Mac上的数据。但是，虽然Apple 的本地备份解决方案非常易于设置(Apple’s local backup solution is super-easy to set up)和使用，但它并不完美。
连接(Connectivity)问题、磁盘错误和许多其他原因可能会阻止Time Machine正确备份数据。
当Time Machine未备份您的Mac时，以下步骤应有助于解决任何问题。具体来说，这些步骤处理以下一组问题：
- Time Machine卡在“准备备份”阶段。
- Time Machine需要很长时间才能完成。
- Time Machine在备份时会导致错误，例如“操作无法完成”。
- Time Machine无法检测到外部驱动器或NAS驱动器。
1. 稍等片刻
您(Did)刚刚在Mac上设置了Time Machine吗？如果内部存储有数百 GB 的数据，您的第一次备份可能需要数小时才能完成。因此，一旦Time Machine在后台运行了较长时间（最好是一夜之间），稍后再检查一次是个好主意。
如果Time Machine仍在准备备份或没有超过特定点，请继续执行以下其他修复。
2.删除备份并重试
停止Time Machine并再次运行它也可以帮助修复卡住的备份。
1. 打开Apple菜单并选择系统偏好设置(System Preferences)。
2. 选择时光机(Time Machine)。
3. 选择进度指示器旁边的x形图标以取消当前的(x)Time Machine备份。
4. 选择Mac 菜单栏上的Time Machine图标，然后选择(Time Machine)立即(Back Up Now)备份选项以重新启动新备份。
提示：(Tip:)如果Time Machine图标不可见，请选中(Time Machine)System Preferences > Time Machine下菜单栏中的 Show Time Machine(Show Time Machine in menu bar)旁边的框以取消隐藏它。
如果外部Time Machine驱动器使用Mac OS Extended (HFS+) file system，您还可以尝试删除包含最近一次备份尝试信息的文件，然后重试。
为此，请打开Finder并选择侧边栏上的Time Machine备份位置。然后，选择Backups.backupdb并选择备份文件夹（它的名称与您的 Mac 相同）。按照此操作，将以 .inProgress(.inProgress)扩展名结尾的文件移动到废纸篓。
3.排除大文件
Time Machine 以增量方式备份您的数据，因此后续备份总是更快。但自上次备份后新添加的大文件（例如，下载的视频）可能会导致不必要的延迟。排除任何非必需品应该可以加快速度。
1. 进入系统偏好设置(System Preferences )> Time Machine并取消当前备份。
2. 选择选项(Options )按钮。
3. 使用加(Plus )号按钮选择要排除的文件和文件夹（例如，Mac 的视频(Videos )文件夹）。
4. 选择保存(Save)。
5. 启动新的Time Machine备份。
4.重新启动Mac并重试
如果Time Machine无法检测到您的备份磁盘、导致错误或继续卡住，请尝试重新启动您的Mac。这会清除过时的系统相关数据，并有效地修复 macOS 中的奇怪问题。
1. 进入系统偏好设置(System Preferences )> Time Machine并取消您当前的Time Machine备份。
2. 打开Apple菜单并选择重新启动(Restart)。
3. 取消选中重新登录时重新打开窗口(Reopen windows when logging back in)旁边的框，然后选择重新启动(Restart)。
完成重新启动后，在菜单栏上选择Time Machine >立即(Back Up Now )备份以重新启动新备份。如果您继续遇到问题，启动 Mac 进入和退出安全模式(booting your Mac in and out of Safe Mode)也可能会有所帮助。
5.删除本地快照并重试
损坏(Corrupt)的本地快照会造成冲突并阻止Time Machine将数据复制到备份磁盘。删除(Delete)它们，看看是否有区别。
1. 打开Launchpad并选择其他(Other )>终端(Terminal)。
2. 运行以下命令并回车(Enter)，调出本地快照列表：
tmutil listlocalsnapshots /
每个快照都包含一个备份日期和标识符，例如2021-09-05-000029。
3. 使用以下命令删除每个本地快照：
sudo tmutil deletelocalsnapshots [备份日期和标识符](sudo tmutil deletelocalsnapshots [backup date and identifier])
删除所有内容后，连接备份磁盘并重新运行Time Machine。
6.更新macOS并重试
内置实用程序已经存在了很长时间，但它仍然容易受到问题的影响。当Time Machine(Time Machine)没有备份 时，更新 Mac 的系统软件可以帮助您解决任何已知问题。
1. 进入系统偏好设置(System Preferences )>软件更新(Software Update)。
2.等到(Wait)您的Mac完成扫描新更新。
3. 选择立即(Update Now )更新以更新您的 Mac。
7.修复备份磁盘
如果Time Machine出现故障、卡住或无法检测到外部备份驱动器，您应该尝试修复它。macOS 中的磁盘工具(Disk Utility)小程序应该可以帮助您。
1. 打开Launchpad并选择其他(Other )>磁盘工具(Disk Utility)。
2.从“磁盘工具”边栏中选择您的(Disk Utility)Time Machine备份驱动器。
3. 选择急救(First Aid)以修复驱动器。
4. 选择运行(Run)。
8.验证备份
如果Time Machine在备份到网络磁盘时失败，验证您以前的备份应该有助于解决文件损坏问题。
为此，请按住Option键并选择菜单栏上的Time Machine图标。(Time Machine)然后，选择验证备份(Verify Backups)。
9.正确连接磁盘
如果您使用外部备份驱动器，但Time Machine无法识别它，请确保您已将其正确连接到Mac。您可能想要切换USB端口并避免将驱动器连接到任何USB集线器。
如果您使用网络磁盘或另一台Mac作为Time Machine目标，请确保您的Mac连接到与其他设备相同的网络。软重置网络路由器(the network router)或更新 Mac 的 DHCP 租约(renewing your Mac’s DHCP lease)应该有助于快速处理与网络相关的意外问题。
10.检查文件系统
首次使用Time Machine设置外置驱动器时，您的Mac会自动使用兼容的文件系统设置它。但是，如果您同时将它连接到另一台计算机，您可能最终会无意中改变它。
如果Time Machine无法检测到驱动器，您可以使用Finder快速检查其文件系统。
1. 按住 Control 键单击桌面或Finder边栏上的备份驱动器。
2. 选择获取(Get) 信息(Info)。
3. 检查Format(Format)旁边的文件系统。如果它没有显示为HFS+（Mac OS 扩展）或APFS（Apple 文件系统(Apple File System)），您必须格式化驱动器（下一节将详细介绍）。
11.格式化磁盘并重试
如果Time Machine在使用特定备份磁盘时仍然存在问题，您必须重新格式化并从头开始设置。但是，这将永久删除Mac的所有旧(Mac)Time Machine快照。
1. 打开Launchpad并选择其他(Other)>磁盘工具(Disk Utility)。
2. 选择您的Time Machine备份驱动器。
3. 选择擦除磁盘(Erase Disk )并将整个磁盘格式化为APFS格式。如果您使用 macOS 10.15 Catalina或更早版本，请改用Mac OS 扩展(Mac OS Extended )格式。
4. 转到系统偏好设置(System Preferences)> Time Machine并选择选择磁盘(Select Disk )选项。然后，选择您刚刚格式化的驱动器并选择完成(Done)。
5. 执行新的Time Machine备份。
修复了 Time Machine 备份的(Time Machine Backups Fixed)问题
大多数与Time Machine备份相关的问题相对容易修复。除非您正在处理严重的文件损坏情况，否则通过一些快速修复（重新启动Mac、停止和启动备份、修复/验证磁盘等）应该可以帮助您让Time Machine进行备份您的Mac再次正确。
Time Machine Not Backing Up Mac? Try These 11 Fixes
Time Machine offers an incredibly conveniеnt way tо safeguard the data on a Mac. But while Apple’s local backup solution is super-easy to set up and use, it isn’t perfect.
Connectivity issues, disk errors, and many other reasons can prevent Time Machine from backing up data correctly.
The steps below should help resolve any issues when Time Machine is not backing up your Mac. Specifically, these steps deal with the following set of issues:
- Time Machine is stuck at the “Preparing Backup” stage.
- Time Machine takes too long to complete.
- Time Machine results in errors while backing up—e.g., “The operation couldn’t be completed.”
- Time Machine fails to detect an external drive or NAS drive.
1. Wait For a While
Did you just set up Time Machine on your Mac? If the internal storage has hundreds of gigabytes of data, your first backup can take hours to complete. So it’s a good idea to check back again later once Time Machine has run in the background for an extended period (preferably overnight).
If Time Machine is still preparing the backup or hasn’t progressed beyond a specific point, continue with the other fixes below.
2. Delete Backup and Retry
Stopping Time Machine and running it again can also help fix a stuck backup.
1. Open the Apple menu and select System Preferences.
2. Select Time Machine.
3. Select the x-shaped icon next to the progress indicator to cancel the current Time Machine backup.
4. Select the Time Machine icon on Mac’s menu bar and pick the Back Up Now option to reinitiate a fresh backup.
Tip: If the Time Machine icon isn’t visible, check the box next to Show Time Machine in menu bar under System Preferences > Time Machine to unhide it.
If an external Time Machine drive uses the Mac OS Extended (HFS+) file system, you can also try deleting the file that holds the information for your most recent backup attempt before retrying.
To do that, open Finder and select the Time Machine backup location on the sidebar. Then, select Backups.backupdb and pick the backup folder (it features the same name as your Mac’s). Follow that by moving the file that ends with the .inProgress extension to the Trash.
3. Exclude Large Files
Time Machine backs up your data incrementally, so subsequent backups are always faster. But newly added large files since your last backup (e.g., downloaded videos) can result in unnecessary delays. Excluding any non-essential items should speed things up.
1. Go to System Preferences > Time Machine and cancel the current backup.
2. Select the Options button.
3. Use the Plus button to pick the files and folders you want to exclude (e.g., your Mac’s Videos folder).
4. Select Save.
5. Initiate a fresh Time Machine backup.
4. Restart Mac and Retry
If Time Machine fails to detect your backup disk, results in errors, or continues to get stuck, try restarting your Mac. That flushes out obsolete system-related data and effectively fixes odd snags and hitches in macOS.
1. Go to System Preferences > Time Machine and cancel your current Time Machine backup.
2. Open the Apple menu and select Restart.
3. Uncheck the box next to Reopen windows when logging back in and select Restart.
After you’ve finished rebooting, select Time Machine > Back Up Now on the menu bar to reinitiate a fresh backup. If you continue to experience issues, booting your Mac in and out of Safe Mode might also help.
5. Delete Local Snapshots and Retry
Corrupt local snapshots can create conflicts and prevent Time Machine from copying data to your backup disk. Delete them and see if that makes a difference.
1. Open Launchpad and select Other > Terminal.
2. Run the following command and press Enter to bring up a list of local snapshots:
tmutil listlocalsnapshots /
Each snapshot contains a backup date and identifier—e.g., 2021-09-05-000029.
3. Use the following command to delete each local snapshot:
sudo tmutil deletelocalsnapshots [backup date and identifier]
After you’ve finished deleting everything, connect your backup disk and rerun Time Machine.
6. Update macOS and Retry
The built-in utility has been around for a long time, but it’s still susceptible to issues. Updating Mac’s system software should help you fix any known problems when Time Machine isn’t backing up.
1. Go to System Preferences > Software Update.
2. Wait until your Mac finishes scanning for new updates.
3. Select Update Now to update your Mac.
7. Repair Backup Disk
If Time Machine fails, gets stuck, or has trouble detecting an external backup drive, you should try repairing it. The Disk Utility applet in macOS should help you with that.
1. Open Launchpad and select Other > Disk Utility.
2. Select your Time Machine backup drive from the Disk Utility sidebar.
3. Select First Aid to repair the drive.
4. Select Run.
8. Verify Backup
If Time Machine fails while backing up to a network disk, verifying your previous backups should help resolve issues with file corruption.
To do that, hold down the Option key and select the Time Machine icon on the menu bar. Then, select Verify Backups.
9. Connect Disk Correctly
If you use an external backup drive but Time Machine fails to recognize it, make sure that you’ve connected it to your Mac correctly. You may want to switch around USB ports and avoid connecting the drive to any USB hubs.
If you use a network disk or another Mac as a Time Machine destination, make sure that your Mac is connected to the same network as the other devices. Soft resetting the network router or renewing your Mac’s DHCP lease should help quickly deal with unexpected network-related issues.
10. Check File System
The first time you set up an external drive with Time Machine, your Mac will automatically set it up with a compatible file system. But if you’ve connected it to a different computer in the meantime, you might’ve ended up changing that unintentionally.
If Time Machine fails to detect the drive, you can quickly check its file system using Finder.
1. Control-click the backup drive on the desktop or Finder sidebar.
2. Select Get Info.
3. Check the file system next to Format. If it doesn’t show up as HFS+ (Mac OS Extended) or APFS (Apple File System), you must format the drive (more on that in the next section).
11. Format Disk and Retry
If Time Machine continues to have trouble with a specific backup disk, you must reformat and set it up from scratch. However, that will permanently delete all older Time Machine snapshots of your Mac.
1. Open Launchpad and select Other > Disk Utility.
2. Select your Time Machine backup drive.
3. Select Erase Disk and format the entire disk in the APFS format. If you use macOS 10.15 Catalina or earlier, use the Mac OS Extended format instead.
4. Go to System Preferences > Time Machine and choose the Select Disk option. Then, pick the drive that you just formatted and select Done.
5. Perform a fresh Time Machine backup.
Issues With Time Machine Backups Fixed
Most Time Machine backup-related issues are relatively easy to fix. Unless you’re dealing with a severe case of file corruption, going through some of the quick fixes (restarting your Mac, stopping and starting a backup, repairing/verifying a disk, etc.) should help you to get Time Machine to back up your Mac correctly again.
