Odds are if you are getting the error “connection failed due to apn settings” when trying to turn on mobile data then you have changed from a 3G or HSPA+ Android phone to one that is true 4G LTE. When you make this transition it is required to contact AT&T and have them update your data plan to support their LTE network. The update that AT&T will perform should take no more than a few minutes and will cost you nothing.

While we explain for AT&T customers this issue can be resolved in the same way with other carriers like Sprint, Verizon and T-Mobile.

How to fix the “connection failed due to apn settings” error:

1. Call AT&T Customer support on Online Chat
2. AT&T will require your phone number and last 4 of your SS#
3. Have your IMEI and SIM numbers available (Settings -> About Phone)
4. Ask them to update your data plan to the LTE network
5. Thats it they will get it working within a few minutes.

Chat log from our support case regarding the error:

Reggie: I’ll be more than happy to assist you, one moment please.
Reggie: Could you provide me with the last 4 digits of the account holders social security number please?
Brandon Orndorff: ****
Reggie: Thank you.
Reggie: Could I get the IMEI number for the device and the sim card number please?
Brandon Orndorff: IMEI is ************ and the SIM number is *********?
Reggie: Are you able to make calls with the device?
Brandon Orndorff: yes I have been making and receiving calls
Reggie: the issue is the system still has an old data plan active on your account. Your device requires the LTE data plan.
Reggie: It is the new LTE service most likely. I will need to update them.
Reggie: Go ahead and power the device down please. It will take me 2-3 minutes to update your account.
Brandon Orndorff: OK the device is off
Reggie: Thank you.
Reggie: I appreciate your patience. I am almost done.
Reggie: Go ahead and power the device up please.
Reggie: Once the device comes back up try browsing to att.com/ttr please.
Brandon Orndorff: works great thank you
Reggie: Have I completely resolved your issue today?
Brandon Orndorff: It seems you have … Thank you