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How to restore original contacts from Time Machine Backup
You can restore contacts with a Time Machine Backup
You may be able to restore from iCloud, using your iCloud account, if it had not been deleted there.

Yes, there is a way to restore Address Book content from a Time Machine backup. However, it’s important to note that Address Book data is used by many applications throughout OS X, so before we begin, make sure to quit all open applications to minimize the possibility of introducing problems.

Steps to restore Address Book content from a Time Machine backup

1. To begin, Disable iCloud sync in System Configuration -> iCloud -> Uncheck Contacts.

2. Now we’ll need to show hidden files in the Finder because the Library folder on the Time Machine drive (as on your Mac) is hidden by default. To do this, open Terminal (located in Applications/Utilities) and type in the following command followed by the enter key (Note: you can re-hide hidden Finder files by replacing “TRUE” with “FALSE” and re-running the command below):

defaults write com.apple.finder AppleShowAllFiles TRUE

Next, restart the Finder by typing the following command:

killall Finder

3. Now open the Address Book contents of your current OS X 10.10 Yosemite by navigating to the following location

~/Library/Application Support/AddressBook

4. Enter the time Machine Backup then Go to ~/Library/Application Support/AddressBook and replace the contents of this folder with the same folder in on your Mac and you are Done.

5. Copy the entire contents of the Address Book folder from the backup and overwrite the contents of this folder on your system drive.
Once the copy is complete, relaunch Address Book and you should see your contacts listed, current as of the date of your last backup.

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