Archived - Time Machine: About "Time Machine completed a verification of your backups. To improve reliability, Time Machine must create a new backup for you."
Apple has identified an issue on some Time Capsule systems that could potentially make previous backups unavailable. The Time Capsule Backup Update improves reliability of affected Mac OS X v10.6 systems by creating a new backup.
After installing the Time Capsule Backup Update, you may see this alert prior to your next scheduled Time Machine backup:
Time Machine completed a verification of
your backups. To improve reliability, Time
Machine must create a new backup for you.
Click "Start New Backup" to create a new backup. This will
remove your existing backup history. This could take
Click "Back Up Later" to be reminded tomorrow. Time
Machine won't perform backups during this time.
Click the "Start New Backup" button to create a new backup. This will remove your existing backup history. This could take several hours. Tip: To expedite the "Start New Backup" process, temporarily connect your Mac directly to your Time Capsule via an Ethernet cable.
Note: If you click "Back Up Later", you will be prompted with the dialog again in 24 hours. Time Machine won't perform backups during this time. You can access the dialog at any time by choosing Back Up Now from the Time Machine menu extra or by clicking and holding the Time Machine icon in the Dock.
Tip: With Mac OS X v10.6.4 or later, you can initiate a verification of your Time Capsule-based Time Machine backups. Hold the Option key and click the Time Machine menubar item. Choose Verify Backup from the Time Machine menu.
If you use Mac OS X v10.5, follow these instructions to determine if you should start a new backup:
Note: This could take several hours so it is recommended that you connect your Mac to the Time Capsule using an Ethernet cable for better performance.
- From the Apple menu, choose System Preferences.
- From the View menu, choose Time Machine.
- Move the slider bar to "Off" to disable Time Machine backups.
- Open Disk Utility located in /Applications/Utilities.
- Open a Finder window and locate your Time Capsule in the "Shared" section of the sidebar.
- Click on the Time Capsule. Enter your password if necessary.
- Locate your Time Machine backup disk image (the disk image will contain the name of your computer in the filename).
- Drag the disk image to the Disk Utility sidebar.
- Select the disk image, then click Verify.
- If Disk Utility reports “Error: File system verify or repair failed,” you need to start a new backup. Note: Do not repair the disk image with Disk Utility.
To start a new backup of your Mac, choose Backup Now from the Time Machine icon in the menu bar.