Verify and update APN ( access point name ) settings for AT&T 4G ( Android )

1. From the Home screen, press the Menu key.
2. Touch Settings.
3. Touch Wireless & networks. Depends on software version
4. Touch Mobile Networks.
5. Touch Access Point Names or APNs.
6. If there is a T-Mobile APN, touch it. If not, press the Menu key, and touch New APN.
7. Verify and update the following settings for the Data APN:  
   • Name: AT&T
   • APN: wap.cingular
   • Proxy: wireless.cingular.com
   • Port: 80
   • Username: WAP@CINGULARGPRS.COM
   • Password: CINGULAR1
   • Server: <Not set>
   • MMSC: http://mmsc.cingular.com
   • MMS proxy: 66.209.11.32
   • MMS port: 80
   • MMS protocol: WAP 2.0
   • MCC: 310
   • MNC: 410
   • Authentication type: <Not set>
   • APN type: <Not Set> 
8. Press the Menu key.
9. Touch Save.