Ten ways to fix Galaxy Note8 “Mobile Network Not Available” bug [troubleshooting guide]

Today’s #GalaxyNote8 troubleshooting guide addresses one of the common network problems any Samsung Galaxy device may encounter — the “Mobile Network Not Available” bug. Be sure to try all our suggestions in the order presented. We hope you’ll find this guide helpful.

Today’s problem: How to fix Galaxy Note8 “Mobile Network Not Available” bug

I am at wits end. I purchased a Note8 from an individual (family member) and it is driving me crazy. It is an AT&T but I have a Straight Talk Sim in it. I have always used AT&T phones and no problems, the phone supposedly worked fine with her AT&T SIM, and my SIM works fine in my old phone which finally completely died today. Not a Sim problem. With correct APN I can pick up my wifi but 95/% of the time I can not make calls, receive calls (nor texts) and it just flat does not pick up my data. It does several different things. It will either actually start dialing then abruptly say “call ended” then tell me “Emergency Calls only” and after reading how to fix that it will switch to Dialing forever and then saying “Mobile Network Not Available” or it will just tell me before even dialing that I am out of service area and Mobile Network not available. Then, it will just all of a sudden every once in a while go bling, bling, bling and all of a sudden my messages that I initiated will send and I will receive messages and I can even dial out. It did that today while I was driving and I dialed out and got the other person but the line started fading, cut out and that was the end of that. I have cleaned everything regarding the sim and have put a little piece of paper on the back of the sim so that maybe the connectors will be closer…. nothing. Currently, I have no phone. HELP…. I think I have pretty much done it all and Straight Talk, AT&T (went to actual store today…. laughable), and Samsung just send me to each other. 🙁 — Christy Turner

Solution: Hi Christy. One of the downsides of using a carrier-branded smartphone on another network is the possibility that some functionalities, even the basic ones like text messaging and voice calling, may not work as expected. That’s mainly because the software on the phone is in conflict with the network setup, or there’s a hardware incompatibility issue. We don’t know the exact phone model of your Note8 but its AT&T software or hardware may not be fully compatible with that of Straight Talk’s network. Keep in mind that Samsung devices built for a specific carrier like your AT&T Note8 runs an AT&T-specific firmware, which may not work properly on other networks. Your Note8’s software codes are only validated with AT&T network so it may or may not work when used outside the parameters of a network it was originally designed for.

To see if there’s something that you can do on your end about this issue, you must do a series of our suggested troubleshooting steps.

Suggestion #1: Ensure you have good signal reception

In many cases, “Mobile Network Not Available” bug appears only when the device is in a poor signal zone. Check your Note8’s signal bars and see if it gets 3 or 4 bars consistently. If it doesn’t, or if the signal is weak (1 or 2 bars only), that means your Note8 is unable to establish good communication with AT&T’s network. In this case, try moving to a well-covered spot befor doing any network action such as texting or calling. Remember, having poor or inconsistent network signal is not a phone issue. You must either move the device to a place with good reception, or do something to improve the situation, like using a signal booster.

Suggestion #2: Reseat the SIM card

You’ve probably done this already before contacting us but if you didn’t, make sure that you don’t skip it. Removing and re-inserting a SIM card forces your device to reconfigure its network settings, including the APN settings. Normally, the current network settings will be overwritten automatically, thereby refreshing all network information. This is an effective way to deal with common network bugs associated with the SIM function so it’s worth trying. If you’ve already tried it, you can just skip this suggestion and proceed to the next one.

Suggestion #3: Manually change the network mode

Some users were able to successfully fix network errors by manually changing their network modes. In a way, this also simulates refreshing network settings so if the cause of the “Mobile Network Not Available” bug lies in the settings, this may be an effective fix. Before changing the network mode, make sure that the phone is using the appropriate network mode. Here’s how:

Open Settings app.
Tap Connections.
Tap Mobile networks.
Tap Network mode and select 4G or LTE or auto-connect (whichever is available).
Once you’ve verified that your Note8 has been using the right network mode all along, try switching to another mode like 2G and let your device use it for a minute. Then, return the device to its ideal network mode and see what happens.

Also, while you’re in it, you can also try to check if the issue goes away if you try to register the device to another network. Under Mobile Networks section, tap on Network operators option and tap on Search networks. Let your Note8 scan the airwaves for sometime and once it comes up with a list of available networks, select one that’s not Straight Talk. You’re Note8 will try to connect and register but obviously fail. After it indicates that it can’t register to that network, connect it again to Straight Talk and see if there’s a difference.

Suggestion #4: Make sure Note8 is not set to “Roam”

Though you did not mention ever setting your Note8 to roaming status, this is one of the common reasons why “Mobile Network Not Available” error occurs. To check, go under Settings > Connections > Mobile networks > Data roaming.

Suggestion #5: Verify Airplane Mode is OFF

Just like enabled data roaming function, enabled Airplane Mode may also lead to “Mobile Network Not Available” error so be sure to check it as well. You can do that by going pulling down the notification bar from the top and tapping on Airplane Mode button. If the error still occurs after turning off Airplane mode, proceed to the next troubleshooting steps below.

Suggestion #6: Install carrier or system updates

In other cases, network issues were fixed only by installing carrier or Android updates. That’s because some forms of network problems are buried deep inside the operating system and it can take a coding patch to fix them. The Galaxy Note8 is set of automatically download and install system updates and in some carrier-branded ones, there’s even no option to block system updates. However, if you have such option and you have a pending system update, make sure to install it to see if that will fix the issue. Remember, “Mobile Network Not Available” error has a network aspect to it as well so there’s a chance an update from Samsung may fix it. If there’s no update at all (because you’re not in AT&T network), just skip this suggestion.

Suggestion #7: Reset network settings

Some network glitches can be effects of incorrect settings. At this point, you can try to refresh the network settings of your Note8 by going under settings. This is the proper way of forcing a device “forget” programmed network configuration so hopefully, this will help fix your issue.

To reset network settings on your Note8:

Open Settings app.
Tap General Management.
Tap Reset.
Tap Reset network settings.
Tap RESET SETTINGS button to confirm.

Suggestion #8: Boot to safe mode and observe

Unless you primarily use pre-installed apps only and did not add anything to the device after setting it up the first time, you can’t totally remove the chance of a third party app causing a problem. The more adventurous you are with your apps, the higher the chance of a bad app causing trouble. To check if one of your added apps is problematic, you need to run your NOte8 to safe mode. Also called as diagnostic mode, this is an independent software environment that functions differently from normal mode in one respect — it blocks third party apps and services from running. So, if “Mobile Network Not Available” error won’t show when on safe mode, you can bet one of the apps is causing a problem.

To boot to safe mode:

Turn the device off.
Press and hold the Power key past the model name screen appearing on the screen.
When SAMSUNG appears on the screen, release the Power key.
Immediately after releasing the Power key, press and hold the Volume down key.
Continue to hold the Volume down key until the device finishes restarting.
When Safe mode appears in the bottom left corner of the screen, release the Volume down key.

If you suspect that an app you added is the reason for the error, you must do trial-and-error to know what that app is. Basically, what you want to do is the following:

Boot to safe mode.
Check for the problem.
Once you’ve confirmed that a third party app is to blame, you can start uninstalling apps individually. We suggest that you begin with the most recent ones you added.
After you uninstall an app, restart the phone to normal mode and check for the problem.
If the problem still remains, repeat steps 1-4.

Suggestion #9: Clear cache and data of Phone and SIM Toolkit apps

At times, bugs with the Phone or SIM Toolkit apps may interfere with Android so the next best thing to do at this point is to clear each of their caches. If clearing the cache won’t fix, then you should try to delete their data.

To clear an app’s cache:

Open Settings app.
Tap Apps.
Tap More settings (three-dot icon) at the upper-right.
Tap Show system apps.
Find the app and tap it.
Tap Storage.
Tap CLEAR CACHE button.
Restart your S9.
Check if the problem still exists.

To clear an app’s data:

Open Settings app.
Tap Apps.
Tap More settings (three-dot icon) at the upper-right.
Tap Show system apps.
Find the app and tap it.
Tap Storage.
Tap CLEAR DATA button.
Restart your S9.
Check if the problem still exists.

IMPORTANT: Clearing the Phone app’s data may delete your contacts and/or call logs. If you want to keep them, consider backing them up first using Samsung cloud or Samsung Smart Switch.

Suggestion #10: Factory reset

If all else fails, the final software troubleshooting step that you can do is factory reset. In your case, doing so will reset all software settings to their defaults, refresh network settings, and clear your personal data. Make sure to back your files first if you don’t want to lose anything. Once you’ve done that, follow the steps below to factory reset your S8:

Turn off the device.
Press and hold the Volume Up key and the Bixby key, then press and hold the Power key.
When the green Android logo displays, release all keys (‘Installing system update’ will show for about 30 – 60 seconds before showing the Android system recovery menu options).
Press the Volume down key several times to highlight ‘wipe data / factory reset’.
Press Power button to select.
Press the Volume down key until ‘Yes — delete all user data’ is highlighted.
Press Power button to select and start the master reset.
When the master reset is complete, ‘Reboot system now’ is highlighted.
Press the Power key to restart the device.

Conclusion

Remember, all our suggestions above are meant to address the aspect of a possible software or app issues on your device. They don’t cover any issues with the hardware, software/hardware incompatibility, and network problems. If nothing works at all, talk to your carrier’s support team and let them figure out where the problem lies. Doing so won’t guarantee that they’ll be able to fix the issue but they may be able to help you identify you. For example, if the main reason for the trouble is due to software on your Note8 being fully incompatible with Straight Talk’s network (remember that your Note8 runs AT&T firmware and not Straight Talk’s), you’re out of luck. That’s a coding issue and there’s nothing Straight Talk can do to change it.