The most common cause is a weak or unstable fiber signal, often because of damaged outdoor cables, incorrect fiber setup, or interference on the line. Other possible reasons include outdated modem software, overloaded modems (especially with older BGW-210 models), or issues with the AT&T system setup on their end. In this guide, we’ll go over the common causes of AT&T Internet problems and walk you through the solutions. But before following these steps, please make sure your AT&T account is registered—especially if your router’s broadband light is solid red.
1. Enable and Disable Network Communications on Your Device
AT&T Internet may not work if your device’s network modules are stuck or need a reset. Simply turning the network communications off and on can help restore the connection.
1.1. Enable and Disable Airplane Mode on an iPhone
1.2. Disable and Enable the Network Connection on a Windows PC
2. Reinsert the SIM Card in Your Mobile Phone
If your SIM card isn’t communicating correctly with the AT&T network, your mobile data might not work. Removing and reinserting the SIM card can help reestablish the link with the cell tower. If this doesn’t work, make sure your phone is compatible with the AT&T network.
3. Restart Your Device and Networking Equipment
If either your device or your network equipment (like your router) is acting up, restarting them can clear up most connection problems.
4. Update Your Phone’s Carrier Settings
If your carrier settings are outdated on your phone, it may have trouble communicating with AT&T’s network towers. Updating these settings often solves mobile data issues. To do this on an iPhone:
5. Clear the Alternate MAC Address (for Xbox)
On Xbox consoles, an Alternate MAC address can sometimes cause connection issues if it’s not needed by your AT&T router. Clearing this address often solves network problems.
6. Update Your Router’s Firmware
If your router’s firmware (built-in software) is outdated, it might not work smoothly with AT&T’s network. Updating the firmware often brings fixes and enhancements that solve connection issues.
7. Disable IPv6 in the Router’s Settings
Not all of your devices or apps may support AT&T’s IPv6 network. If there are compatibility problems—or if AT&T’s IPv6 DNS servers aren’t responding—disabling IPv6 in your router settings is a good step.
8. Disable AT&T Internet Security on the Router
Sometimes, AT&T Internet Security (built into the router) might mistakenly block some devices or web pages. Temporarily turning off this feature can help identify if it’s the cause. If that doesn’t help—and a VPN is running on any device attached to your AT&T network—try turning off VPN on all devices. This can also resolve Internet issues.
9. Restore and Re-add the APN Settings on Your Phone
Access Point Name (APN) settings control how your mobile device accesses the Internet. If they’re incorrect, your mobile data will likely stop working. You can reset or re-enter these details as follows (on Android):
10. Change the DNS Settings of Your Devices
If your DNS (Domain Name System) isn’t set up properly, your devices won’t know how to reach websites. Changing your DNS to a well-known public service can often help (such as Google DNS). If that still doesn’t help, changing the DNS in your router’s admin settings might do the trick (though it can affect AT&T Uverse devices).
11. Reset the Network Settings
Your device’s saved network settings can sometimes get corrupted or overloaded with incorrect data. Resetting them can give you a clean slate. Be sure to write down any Wi-Fi passwords or other settings you might need to re-enter later.
11.1. For iPhone
11.2. For Windows PC
For issues on a car (such as a Nissan), try resetting the car’s location settings. On a Mac, you can try renewing the DHCP lease in Network Preferences.
12. Reset the Router to Factory Defaults
If your router’s firmware is storing conflicting or incorrect data from AT&T, resetting it can fix many Internet issues.
13. Reset the Device to Factory Defaults
If one device (like your phone) can’t get online with AT&T, and all other devices are fine, the problem could be inside your device’s software. Resetting it to factory defaults can usually solve this. Note: Resetting to factory defaults deletes all data. Make sure you back up everything important first. To reset an iPhone: If even after this the device doesn’t connect, try using a different router with AT&T. If you’re using a third-party router, you can put your AT&T router in passthrough mode. If you’re still stuck, your device could be faulty—in which case, try a replacement. For issues outside your control, contact AT&T support. If the problem is not fixed, you can file a complaint with the FCC.
