1 Answer

Instructions
Microsoft Outlook

1
Click the "File" menu at the top-left corner of the Outlook window, click "Open" and click "Import."

2
Click "Import from Another Program or File" and click "Next."

3
Click "Personal Folder File (.pst)" and click "Next."

4
Click "Browse," browse for the .pst backup file containing the email contacts, double-click it and click "Next."

5
Click the "Contacts" folder and click "Finish."

Gmail

6
Click the "Contacts" link at the upper-left corner of the Gmail page.

7
Click the "More Actions" button at the top of the list of contacts and click "Restore Contacts."

8
Select a time you want to restore your contacts to by clicking one of the options and click "Restore."

Mozilla Thunderbird

9
Close Thunderbird if it's running by clicking "File" and "Exit."

10
Click "Start" and "Computer."

11
Click "Organize" at the top-left corner of the Computer window and click "Folder and Search Options."

12
Click the "View" tab, click "Show Hidden Files, Folders and Drives" and click "OK."

13
Navigate to the "C:\Users\User Name\AppData\Roaming\Thunderbird\Profiles" directory, where "User Name" is the name of your Windows user account.

14
Double-click the profile folder name ending in ".default."

15
Copy and paste the "abook.mab" and "history.mab" files from a Thunderbird backup into the profile folder. 

http://www.ehow.com/how_7824561_restore-email-contacts.html