HOW TO RESTORE/RECOVER DELETED CONTACTS FROM ANDROID PHONES?
http://www.android-mobile-manager.com/resources/recover-deleted-contacts-from -android-phones.html
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When a "delete" is performed, only the space that the file occupies is marked as blank and can be reused by new files, but the deleted file will be still there until new data overwrites it. Hence, if you delete some important contacts un consciously, don't worry, you still have a chance to get the deleted phone nu mber, email address, company address or more come back since we have Android Contacts Recovery software.
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This tool is the magical recovery tool designed to recover all deleted or lost c ontacts, SMS files from all kinds of Android smartphones, including Samsun g Galaxy series, HTC One series, LG Optimus series, etc. With it, you can ge t full access to the phone's internal flash card and it will help you deeply scan your device and display all deleted and existing data on the program for your reference.
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Now, just download the free trial version and restore Android contacts now!
Step 1. Run the Program and Connect Your Phone  To begin with, link your Android phones into the computer and be sure that t he USB debugging is opened. Then launch the program and it will start scann ing for files on your Android mobile phones. 
Below is the tips for you to open the USB debugging: 1) For Android 2.3 or earlier: Enter "Settings" < Click "Applications" < Click "Development" < Check "USB debugging" 2) For Android 3.0 to 4.1: Enter "Settings" < Click "Developer options" < Ch eck "USB debugging" 3) For Android 4.2 or newer: Enter "Settings" < Click "About Phone" < Tap "Build number" for several times until getting a note "You are under develop er mode", Then you may back to "Settings" < Click "Developer options" < C heck "USB debugging".
Step 2. Preview and Mark the Files You Want to Restore ď&#x201A;˘ Contacts will be scanned and divided into the related folder in the left panel. You can choose it and then you can preview the detailed contents in the right panel, including Name, Phone number, Company, etc. Just mark the contacts you want to restore one by one. ď&#x201A;˘
Step 3. Begin to Recover When you have marked all data you need, you can click "Recovery" button t o save all your selected files on your computer.
Related Article ： How to Recover Deleted Text Messages from Android How to Root Android Phones & Tablets How to Recover Deleted Photos, Videos from Android Phone