I go to Settings > Mobile Data > Access point names > ATT phone (the only option): all of the information is locked. I can't edit anything. I can take screenshots if necessary.
EDIT: However, Settings > Mobile Data > Access point names: I can hit the menu button for 'New APN' or 'Reset to default'. Should I Reset to Default and see if it does anything?
I have no idea if you should reset or not as mine came without APNs and I had to enter it manually. But AT&T has several MMS APN settings. You can try each one and check. *
Name: Cingular 410
APN: wap.cingular
Proxy: Blank
Port: Blank
Username:
WAP@CINGULARGPRS.COM
Password: CINGULAR1
Server: cingulargprs.com
MMSC:
http://mms.cingular.com
MMS Proxy: wireless.cingular.com
MMS Port: Blank
MCC: 310
MNC: 410
Authentication type: Blank
APN Type: default,supl,mms
APN protocol: leave as is
Bearer: leave as is
Name: phone
APN: phone
Proxy: Blank
Port: Blank
Username: blank
Password: blank
Server: blank
MMSC: blank
MMS Proxy: blank
MMS Port: blank
MCC: 310
MNC: 410
Authentication type: Blank
APN Type: default,internet,supl
APN protocol: leave as is
Bearer: leave as is
Name: AT&T
APN: pta
Proxy:
Port:
Username:
Password:
Server:
MMSC:
http://mmsc.mobile.att.net/
MMS Proxy: proxy.mobile.att.net
MMS Port: 80
MCC: 310
MNC: 410
Authentication Type:
APN Type: default,admin,fota,mms,supl,hipri
APN Protocol: IPv4/IPv6
APN Roaming Protocol: IPv4/IPv6
Name: pta
APN: pta
Proxy: Blank
Port: Blank
Username: blank
Password: blank
Server: blank
MMSC: blank
MMS Proxy: blank
MMS Port: blank
MCC: 310
MNC: 410
Authentication type: Blank
APN Type: default,internet,mms,supl
APN protocol: leave as is
Bearer: leave as is
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