However, as for iPhone, you may easily lost your contacts in casual, such as accidently deletion, formatting, restoring to factory setting, jailbreak, update, downgrade, theft, damage and so on. You can restore them with easily if you have a backup, unfortunately, you didn't. Instead of praying to god, no better than find an efficient way practical. iPhone Data Recovery is a good way to go.
Under What Circumstances You need to Recover iPhone Contacts
iPhone Damaged
----- Damaged by liquid, you cannot do anything in order to remedy water or rice damage.
----- Don't take a hair dryer to a water damaged iPhone, it may cause corrosion and potentially damage device further.
iPhone Stolen - It's possible to recover lost contacts from iPhone 6/6 Plus/5S/5C/5/4S/4/3GS. If you backup iPhone with iTunes before.
Failed to jailbreaking - It's extremely dangerous to jailbreak the iPhone, so, stay away from this upgrade.
Step 1. Choose your iPhone's backup to scan it
When you run the program, choose the recovery mode of "Recover from iTunes Backup File" on the top. Then it will automatically find your iTunes backups and show them in the window as follow. Choose one for your iPhone and click "Start Scan".
When the scan is over, you can preview your previous contacts before recovery, to confirm if they are what you really need. Then mark them and click "Recover" to save them on your computer.
Step 3. Restore iPhone contacts from backup
The contact you saved on your computer is separately in CSV, VCF and HTML format. Now you can restore the contacts (the CSV format one) to your iPhone via Windows address book.
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