How to Transfer Contacts From an AT&T SIM Card to T-Mobile
- 1). Remove the battery cover and battery from your AT&T phone. Insert the AT&T Wireless SIM card in its SIM holder. Turn on your AT&T phone. Navigate to the address book application. Press the menu key and click "SIM phone book." Press the menu key again and click "Copy to Phone."
- 2). Launch the AT&T Mobile Backup application from your phone. Click "Backup" to begin synchronizing your phone's contacts with the Mobile Backup Web interface.
- 3). Log in to your AT&T Wireless Mobile Backup account in your computer's Web browser. Click "Export Contacts" from the AT&T Wireless Mobile Backup Web interface. Follow the screen prompts to create a backup file for your address book and save it on your computer's hard drive.
- 4). Log in to your T-Mobile USA Mobile backup Account in your computer's Web browser. Click "Import Contacts" from the home page. Follow the screen prompts to select the backup file you created in Step 3 and upload it to the Web interface.
- 5). Browse your T-Mobile USA handset to ensure that the SIM card contacts auto-synchronized with the handset's address book.
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