The Subscriber Identity Module, or SIM card, is a mobile device’s “brain.” This chip enables the device to make and receive phone calls, as well as send and receive text messages and connect to a mobile network. Your device’s key features are lost when it has an invalid SIM card.

This is why it’s critical to learn how to troubleshoot SIM card problems on your own. The methods range from basic to complex, but our guide will teach you the most convenient options.

Invalid SIM Card or No SIM Error: What Are the Causes?

Before attempting to remedy the problem, you must first understand what an invalid SIM card or no SIM error means.

It’s possible to get an invalid SIM card or a no SIM error at any time. It happens whether you’re using an Android or iOS device. When your device displays the notifications “invalid SIM card,” “no SIM card,” or “SIM card not detected,” you’ll know there’s an issue.

There are a variety of reasons why a SIM card is invalid or the mobile device is unable to recognize it. To begin with, there could be a problem with the SIM card itself. It’s possible that the chip is damaged or that it’s not properly seated in its designated slot. Second, there could be problems with the hardware. The SIM card-reading component of your device, for example, is broken.

Additionally, there may be software issues. For example, your device may be running an outdated version of Android or iOS, or it may have malfunctioning apps. Finally, your phone may not be network-unlocked, which explains why it won’t function with different SIM cards.

You won’t be able to pinpoint the exact problem right away because it will be determined by which solution works. Fortunately, you may try a variety of remedies for your Android and iOS devices.

How to Fix Invalid SIM card or No SIM Error?

The invalid SIM card or no SIM problem can be solved in a variety of ways. You have the option of selecting your preferred method. In most circumstances, you’ll have to attempt a few different solutions. As a result, we’ve previously included every known remedy that works, which are all pretty similar fixes for when your phone fails to recognize your USB or does not read your SD card. For both Android and iOS, the methods are detailed.

1. Reboot Your Device

Unlike in the past, there’s no need to smack an unresponsive device to get it to operate; all you may need to do is turn it off and on again. Minor issues, such as SIM troubles, lags, and crashes, can be resolved by restarting your device.

Rebooting has advantages. It pauses operating apps and clears the RAM, which is the temporary store for data of running programs. As a result, your gadget is restored to a “fresh” state after being overwhelmed with data.

This solution only has drawbacks if you use it excessively. The lifespan of a device can be shortened as a result of repeated rebooting. As a result, technological experts advocate simply restarting a phone once a week.

Simply press and hold the power button to reboot an Android device. Instead of manually shutting it down and turning it back on, choose “Restart.”

Press and hold the volume and/or the independent side or top button to restart an iOS device. To turn it off, drag the slider. When the device has finished shutting down, switch it back on. You must push the side button once more until the Apple logo appears.

2. Re-Insert SIM Card

Another solution to the SIM card error problem could be to remove and replace the SIM card. It will work if the invalid SIM card issue is caused by a misalignment. When withdrawing and re-inserting the SIM card, be careful not to scratch it. If this occurs, the problem may worsen.

Take the following steps:

1. To eject a SIM card from an Android or iOS device, turn it off first.

2. Look for the SIM card tray. For many of the newer versions, it can be located on either side of the device.
If necessary, either open the slot or use the proper SIM removal tool.

3. Push the protruding end of the SIM removal tool gently into the little hole. The tray will eject automatically if the closure loosens on its own.
* The SIM card is located beneath the battery in older devices. To access the tray, simply remove the back cover and battery.

4. Remove the tray and/or the SIM card.

5. Adjust it exactly before replacing the tray.

After that, turn on your phone and check to see if the SIM card is now active or detected.

3. Switch to Supported Network Operator

The network operator settings may have been toggled, which is another reason why the SIM card cannot be read by the device. Make sure you’re connected to the right network for your device and SIM card.

Take the actions outlined below.

1. Go to the Settings menu on an Android device to check on it.

2. Then select “Mobile networks” from the “Connections” menu.

3. Select “Network operators” from the drop-down menu.

4. Select the “Search network” option, then “Select manually” and select the appropriate network from the list.

5. Open the Settings menu on your iOS device to choose a network. Select “Cellular” from the drop-down menu.

6. Among the options, select “Cellular Network.”

7. Toggle the “Automatic” slider to the left. This will turn off the device’s auto-searching network capability and compel it to rescan for available networks right now. Choose the appropriate network from the list that appears.

4. Reset Network Settings

Resetting network settings is a common solution for connectivity issues, but it can also be used to solve the problem of an invalid SIM card.

If you reset network settings, only the Wi-Fi, cellular network, and Virtual Private Network (VPN) will be reset to default. Make a list of your Wi-Fi, cellular network, and VPN names and passwords ahead of time because you’ll need to adjust them afterward.

Follow these methods to reset network settings on Android devices:

1. Select “General Management” from the Settings menu.

2. Reset the network settings by tapping “Reset” and then “Reset network settings.” The functions affected by the reset will be listed on your smartphone. Select “Reset Network Settings” if you’re alright with it.
*If the above instructions do not apply to your device model, there is another option. On the Settings menu, select “System.” Choose “Advanced.” Choose the “Reset Wi-Fi, Mobile & Bluetooth” option under “Reset Options.”

To perform the same on an iOS device, follow these steps:

1. Turn off your iCloud Keychain first to avoid losing your credentials across all of your iCloud-registered devices.

2. Start by going to the Settings menu.

3. Then tap “General” and “Reset.” You’ll be presented with a number of reset alternatives as a result of this. Choose “Reset Network Settings” from the drop-down menu. If necessary, enter your passcode. Allow for a reboot of the gadget.

There should be no dangers in resetting your devices’ network settings unless you forget to back up your network credentials.

5. Switch Airplane Mode On and Off

When traveling by plane, Airplane Mode is a typical setting. It disables your cellular network so that you don’t interrupt the aircraft’s signal or communication throughout the flight. The mode also saves the battery life of your device by reducing the amount of power it uses to hunt for signals.

When Airplane Mode is turned on and off, the device’s network settings are refreshed. This works in the same way that scanning for a mobile network does. As a result, your device looks for a network that matches your SIM card once more.

Swipe down on your Android device’s home screen to activate Airplane Mode. You’ll see a variety of icons there, each with a particular function. The one that looks like an airplane should be tapped. Wait for it to activate for a few seconds, then click it again to turn it off.

On an iOS device, swipe down from the top-right corner of the home screen to activate Airplane Mode. Select the airplane icon from the drop-down menu. After a few seconds, tap it again. You may also turn it on and off by going to the Settings menu and selecting “Airplane Mode.”

6. Activate Safe Mode

Once in Safe Mode, a device will reboot and all third-party apps will be disabled. When the problem is a faulty app, this can help solve the invalid SIM card or No SIM issue.

It only takes a few steps to activate Safe Mode. Make a long push on the power button on Android. Press and hold the “Power off” icon when it appears. After that, the “Safe mode” icon will appear. To restart the device in Safe Mode, tap on it. To turn off Safe Mode, simply restart the device.

To turn off an iOS device, press and hold the power button. To turn the gadget on, repeat this procedure. When the screen comes up, press and hold the power and volume buttons at the same time until the Apple icon appears. Safe Mode will be on by default. Simply restart the device to turn it off.

If the controls differ somewhat depending on your device type, you may easily find the particular instructions on the help website of your mobile device manufacturer.

7. Update Software

You can get the most recent features by updating the software on your device. It also corrects or patches any flaws that may have contributed to the invalid SIM card problem.

To upgrade your Android device’s software, you’ll need an active internet connection. This can be a Wi-Fi network or a mobile network. The former is the better option.

Once you’ve connected to the internet, go to the Settings menu. Select “Software Update” from the drop-down menu. Select “Download and install,” and the device will download the most recent version of Android and install it when you’re ready.

Connect to Wi-Fi or a mobile network to get the newest version of iOS. Select the Settings option from the drop-down menu. On the iOS version description screen, tap “General,” then “Software Update.” Finally, tap the “Download and Install” option. To apply the update, click “Install.” If the process requires it, enter the device passcode.

Updating software has no negative consequences for your device. Because no program is perfect, new problems may arise over time.

8. Factory Reset

One of the last alternatives for resolving the invalid SIM card or no SIM problem is to do a factory reset. When no other simple ways work, users of mobile devices turn to this.

However, proceed with caution because a factory reset will erase all information, data on the internal memory, apps, and the device’s existing settings. The result is the default condition of your device when it was first purchased.

As a precaution, make sure you’ve backed up all of your crucial data and files to a flash drive or the cloud, and that the device is well charged. This is due to the fact that data will be deleted, and the procedure can take many hours to complete.

Go to the Settings menu on an Android device to factory reset it. Select “General Management” from the drop-down menu. If you don’t see “Privacy” or “Backup and Reset” on your menu, press “Privacy” or “Backup and Reset.” If you’ve made your mind, click “Reset” or “Factory Data Reset.” If Factory Reset Protection is activated, you may be asked for your Google account password.

Physical buttons can be used to factory reset an Android device, although it is better to navigate through the Settings menu to avoid inadvertent operations.

You’ll also need to go to the Settings menu to factory reset an iOS device. Choose “General” and then “Reset.” From the list of reset choices, select “Erase All Content and Settings.” After that, the device will reboot.

The button shortcuts that work on older iOS versions, via iTunes, and third-party software techniques are also options for doing an iPhone factory reset.

9. Call Customer Help Hotlines

If your phone does not recognize the new SIM card you put in it, the issue is most likely with your mobile device. This is the time to seek professional assistance. You can seek advice from specialists by calling the customer service hotlines of your mobile device carrier. The manufacturer’s website will usually have contact information.

Customer care staff from your mobile device provider may be able to assist you with more troubleshooting suggestions or referrals to the local service center. This depends on how serious the condition is when assessed.

10. Replace the SIM card

If all else fails and the invalid SIM card or no SIM error persists, the SIM card should be replaced. Check to see if the SIM card is the source of the issue. You can do this by adding a second SIM card into your phone. If the alternative SIM card functions well, your original SIM card is faulty.

SIM Card Care Tips

It is preferable to prevent than cure. By taking care of your SIM card, you can avoid the problem of an invalid SIM card. Here are a few pointers.

Avoid Frequent Swapping

To begin, avoid swapping your SIM card frequently because it may scratch it. To install and remove it correctly, refer to the handbook. It’s also a good idea to have multiple SIM cards for each device so you don’t have to transfer frequently.

Don’t Touch the Chip

Avoid contacting the data-containing chip or gold contact. You expose it to perspiration when you touch it repeatedly. Moisture can cause corrosion, which has a negative impact on how the SIM card functions and is detected by the mobile device.

Don’t Cut the SIM Card

Do not attempt to cut the SIM card into micro or nano size on your own. Making precise cuts is tough without the correct tool or machine. You might even cut what isn’t supposed to be cut, irreversibly ruining the SIM card. Simply take it to a mobile device retailer and have it cut using the right equipment.

Store It Properly When Not in Use

If you’re not using your phone, keep the SIM card in a safe place. A safe environment is one that is free of liquids, severe temperatures, and magnets. Rusting is caused by liquids and high heat, and strong magnets, for example, might alter the data in a chip. Keep the SIM card in a safe place where you won’t lose it.

Clean Carefully

Finally, if the SIM card needs to be cleaned, do it correctly. Place your SIM card on a clean, dry place. Using a smooth cloth, cotton balls, or Q-tips, gently blow off the dust. You can also use a cleaning pen to lightly rub the card. Water, toothpaste, soap, or chemicals should not be used.

Final Thoughts

You may save time and money by learning how to diagnose or solve the invalid SIM card or no SIM problem on Android and iOS devices. This is because there is no longer a pressing need to buy a new SIM card or mobile device and wait for repairs at a service facility. Those solutions are best used in conjunction with proper maintenance to ensure that your SIM card and device are always in good working order.