What is an MMI code: removing the error on an Android device. Error “Invalid MMI code” on the phone - what does it mean, how to fix it? What is MMI code

When performing USSD requests, various types of errors may occur. A very common situation occurs when, after sending a request, a notification “Connection problems or incorrect MMI code” appears on the screen. MMI is a query generation code used to connect the user and operator. Sometimes this process fails and an error appears in front of you. We will talk in detail about how to fix it in our article.

Method for correcting the error “Connection problems or incorrect MMI code.”

Reasons for the error

This phenomenon may occur in your phone due to incorrect settings or due to a malfunction of the SIM card. First, you should try to fix the problem yourself, but if this fails, then it’s time to turn to your mobile operator for help. An incorrect MMI code may appear when using any operator: MTS, Beeline or Megafon. The brand of the device also does not affect this process, however, it has been noticed that on Android devices, in particular from Samsung, this problem occurs more often. However, most likely this is due to the fact that this brand of gadgets is in great demand.

Invalid MMI code: how to fix

Method 1: Retry the request. Sometimes you get an error when entering a request, but you do not experience any problems with communication. In this case, you should repeat the input after a while, since, most likely, your operator is to blame for the failure.

Method 2: Turn on airplane mode. Airplane mode can disable many functions. If you are experiencing connection errors on your Android, then open the top panel and switch airplane mode to the active position for a few seconds, then turn it off. After this operation, everything should fall into place.

Method 3: Reboot your smartphone. If turning on Airplane mode did not help you, rebooting your device may resolve the connection issue or invalid MMI code. Reboot or turn your gadget on and off, then check it for a malfunction.

Method 4: Change the network type. Modern devices can work with 4G communications. However, it does not always work stably on Android. This can be understood by the change in the inscription next to the communication stripes. The question arises - what to do? If you are faced with exactly this situation, then you need to change the network type:

• open Settings.
• go to " Wireless network» – « Mobile networks" – "Network type".
• select the 3G option, if it does not meet the requirements of your region, then select 2G, then everything can be returned to its place.

Check if your queries are working now.

Method 5: Change SIM card. Sometimes the SIM card gets damaged and loses its main function. In this case, you need to contact the cellular center for new card. Contacts located on your old SIM card and those that were not saved to the phone memory will be deleted. If you purchased new SIM card, but the error occurs again and again, check whether you have placed it completely in the appropriate slot. You can also remove the card and put it back in place again. You can also check the quality of its work on another smartphone.

Method 6: Put your phone in safe mode. Sometimes third-party applications can affect some processes in the device. To determine whether a “foreign” program is to blame or not, you need to go into safe mode. To begin, hold down the power button on your phone. Then, in the menu that opens, hold your finger on the “Shutdown” item. A dialog box will appear in front of you, informing you that you have entered safe mode. After clicking "OK" your phone will be launched. It will contain only system programs. Therefore, you will be able to determine whether a third party is at fault software or not.

If none of the methods described above helped you, then you should contact your operator. Most likely, some work is being done on the server.

We hope that our article helped you. If you have any questions, ask them in the comments.

It happens that when you try to call, send an SMS or make a request to the operator, your phone displays a message "Connection problem or invalid codemmi» . This message may appear at the most inopportune moment and cause a lot of inconvenience, especially when your business is urgent. In this article, I will tell you what this problem of incorrect MMI code is, and also share the best methods on how to fix connection problems or incorrect MMI code, making sure that your Android phone works for a long time and reliably.

Code MMI(Man-Machine Interface) is used to formulate USSD requests that allow organizing interactive interaction between network subscribers and operator service applications. The user uses MMI to find out the balance, top up the account, connect or disconnect any service, switch to another tariff plan, and so on.

Typically, the MMI code begins with an asterisk and ends with a hash; for complex queries, an asterisk is also used as a separator.

Connection problem or invalid mmi code - causes and solutions

This error can occur on different mobile operators and on different mobile devices, manifesting itself in the form of the message “Connection problems or invalid MMI code”, “Invalid MMI code”, “Connection problem or invalid MMI” and others.

Often, a problem with the mmi code appears suddenly, and just as suddenly it can disappear, leaving the user at a loss about the real sources of its occurrence. Below I will list existing reasons occurrence of the problem, and also tell you how to troubleshoot the problem.

Unstable operation of the operator's 3G networks

The operation of today's 3G networks in Russia, Ukraine and other post-Soviet countries is still far from ideal. There are failures, signal loss, unreliable operation of equipment and other troubles that manifest themselves on your device in the form of switching the network icon from 3G to 2G and back.

To solve the problem of connection problems or incorrect MMI code, simply disable the 3G connection for a while, giving your operator time to fix the problem.

Physical wear of the SIM card causes connection problems or incorrect MMI code

One of the most common problems. If your SIM card has been in use for many years, or is often removed and inserted, then it may lose its functionality due to wear and tear. Try connecting it to another phone and checking its functionality. If another phone has a similar problem with an incorrect MMI code, then you can try wiping its contacts, and if the problem continues, contact your office mobile operator for a replacement (experts recommend changing your SIM card every 2 years).

Problems with device settings

Incorrect device settings or malfunctions may cause a problem - connection problems or incorrect MMI code.

1. Try rebooting your device, and if the problem persists, try full reset data.
2. Go to “Settings” - “Backup and reset” - “Data reset” - “Device reset” (otherwise “Settings” - “ Backup" - "Reset data").

Temporary problems with the mobile operator

In this case, all you have to do is wait. You can call the operator and find out how long the error with MMI will persist.

Some applications work

Some externally downloaded applications may cause an error with connection problems or an incorrect MMI code. To confirm or refute this suspicion, boot your device in safe mode and try to make a request to the operator. If it goes well, it means that some new application installed on the phone is to blame and will need to be removed.

Find out how on your device on the website of the manufacturer of your gadget. On mine, Samsung, it’s done like this.

• First you need to turn off the device, then press its power button, and after the device turns on, you need to hold down the “Volume Down” button for a few seconds (while the developer logos are being displayed).
• After these steps, your smartphone (tablet) will boot into safe mode (you will see a message about this at the bottom of the screen), and you will be able to test its operation.

Conclusion

As we can see, connection problems and incorrect MMI code are usually caused by instability of mobile operator networks, as well as physical wear and tear of the SIM card. The causes of the problem may include incorrect phone settings, as well as third-party applications that can cause malfunctions mobile device. If you see a similar error, then first of all, try contacting your mobile operator - it is quite possible that the reason is not yours, but his.

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Typical for smartphones that are trying to send a request to check an account, the amount of traffic, or similar actions. In general, MMI is translated as “Man-Machine Interface”. The interface is generated upon sending USSD requests.

USSD requests are those for which, when sent to the operator, the robot generates data that is relevant only to you, for example, a balance. Thus, interactive interaction with the operator occurs mobile communications. USSD requests are typically preceded by an asterisk and a closing pound sign.

Incorrect connection or incorrect MMI code - reasons

The reason that problems occur, including an incorrect MMI code, may be the phone itself, which has incorrect settings, or a failure may occur due to incorrect operation of the SIM card. You should first try to fix the problem yourself, and if there is no positive result, contact the operator for help.

Usually the error appears at the stage of forming the request, that is, it has not even been sent to the operator’s robot yet. Accordingly, somewhere at the stage of creating the necessary request, a failure occurred or the network was unable to transmit it.

The appearance of the error is not affected by the type of operator or smartphone/phone model, the problem is somewhat detached from these factors, however, an increased number of similar errors have been noticed on Android, and in particular Samsung smartphones. Most likely, this state of affairs is caused by the widespread use of brand gadgets.

Connection problems or incorrect MMI code due to smartphone settings

Now let's look at the incorrect MMI code and what to do. Initially, you should check, probably the reason is a simple settings failure. If the error appeared once, then you can try sending the message again after a short period of time. When there is still no positive result, you should make sure that you are entering the correct code. Information about verification codes is available on the operator’s website.

A small trick that often helps is changing the notification mode:

1. Expand the list of settings by swiping from top to bottom;
2. Activate airplane mode;

1. After a short time, about 30 seconds, turn off the mode and repeat the procedure of contacting the operator.

If this maneuver does not work, you should restart your smartphone. Hold the "Power" button for 10 seconds, then turn on the phone. In case of failures in the settings, the action should work.

Additionally, you can reset the settings to their original state, for this you use either the smartphone function of the same name or recovery mode. The first is a more gentle option, the action is performed like this:

1. Go to “Settings” and select “Backup and reset”;

1. Next, click on “Data reset”, and then “Device reset”.

Invalid MMI code on Android - manual network installation

Modern gadgets have long learned to work with 4G communications; it is very fast and advanced, but equipment modernization on the part of the operator slows down progress somewhat. Thus, an unstable connection may occur, then the smartphone will independently change the technology to another one that is currently available.

Such automatic transitions negatively affect the quality of communication and may be accompanied by interruptions. The problem is indicated by a changing inscription near the display of the number of antenna rods. You should independently set a more stable communication format, even if it is less progressive. To do this you need:

1. Go to "Settings";
2. Expand the full list using the “More” button;
3. Follow the link “Wireless Networks”;
4. Next, select “Mobile networks”;
5. Click on the “Network type” parameter;

1. It is recommended to make the 3G point active; if it does not meet the requirements due to the terrain in the region, then change it to 2G.

The coating should now be maintained at the same level and the cause of the error can be eliminated.

SIM card wear

Unfortunately, there are situations when, due to mechanical deformation or prolonged use, the SIM card is no longer able to perform its direct function - to maintain communication. In this case, you will have to contact service center for a new card. In this case, contacts that were recorded only on the card memory will disappear.

If the error appears after the next SIM card change, don’t be upset, you probably just didn’t insert the card all the way. Try removing it and installing it again. Sometimes the contacts become somewhat deformed, so that a gap is created, generating an obstacle to communication. This may also cause the card or battery latches to break. You can check the functionality of the SIM card on another phone.

Replacing the card if you apply with identification documents is a quick procedure, and you will be able to keep your number.

Conflict over applications

Some programs are unable to function properly in general or in a specific environment. Such applications cause all sorts of problems, including with the network. To check whether you really have this problem, you should start your smartphone in safe mode. This way, no secondary programs are launched. To initialize this mode, during the startup process, you should hold down the “Menu” button until the smartphone is completely loaded, and the action will be accompanied by a corresponding inscription.

If the error disappears, then the application is the culprit. Conflicts between the FX Camera program and the network have been observed, otherwise you will have to sequentially go through the extensions until the cause is determined.

In the end, if the problem still persists, then you can confidently point the finger at the network operator. Most likely he is carrying out work, modernization, etc. online. Then there is nothing left but to wait for a solution to the problem on his part.

If you still have questions on the topic “Wrong connection or incorrect MMI code - how to fix the error?”, you can ask them in the comments

Sometimes smartphone owners are faced with the fact that a message in English “Connection problem or invalid MMI code” appears on the screen of their mobile device or in Russian “Connection problems or incorrect MMI code” on Xiaomi. This situation occurs if the user tries to send a short message, i.e. generate a USSD request. This means that it becomes impossible to connect/disconnect the service, switch to another tariff and use other services of the mobile operator.

The problem can be solved in several ways, which we will tell you about.

Changing settings and rebooting your phone

If an error occurs on the display, it is recommended to restart your smartphone. If after this action it is still impossible to generate a USSD request, then you need to go to “Settings” and select “On the plane”. You can also activate the mode by lowering the curtain on the main screen and selecting the desired option among the icons. After 10-15 seconds, you should deactivate the mode and check if the error remains.

Activating Safe Mode

If some application was recently installed, it could cause the device to malfunction. The optimal solution in this case is to include safe mode. To do this, you need to turn off the device, and then hold down the volume down and power buttons for a few seconds. An image of a branded hare will appear on the screen and an inscription stating that the function we need is activated.

If information about an incorrect MMI code does not appear on Xiaomi, then you need to restart the phone and find the program that causes this error. Naturally, the found utility must be removed.

Checking the signal level

If the mobile operator's signal is unstable, weak or absent, sending a request is not possible. The fact that the signal is too weak will be indicated by a change in information about the connected network on the display: either 3G, then EDGE, etc. In this case, you can try going to “Settings” - “SIM cards and mobile networks”.

In the window that appears, select the name of your mobile operator and indicate the preferred network type - 2G or 3G.

Roaming

It happens that a Xiaomi smartphone in another country is configured to cover the local operator, as a result of which sending requests to its network becomes impossible. You can use the above sequence of actions and select “Mobile networks”. Instead of automatically selecting a network, you should choose your operator. If this does not help, then all you have to do is contact support to clarify the issue.

A much less common situation is when the “Invalid MMI code” message on Xiaomi becomes a consequence of the SIM card not working. Only replacing it will help.

USSD services are long-established standards for communication between subscribers cellular networks with service servers. Sending USSD messages is reminiscent of communicating with bots on Telegram and other services where they are widely used. By sending a command, the user receives a response - this can be certain data or information about the execution of the requested service.

Many smartphone and telephone users do not even imagine what a USSD interaction service is, although they regularly use it. Checking your balance, changing your tariff plan, connecting services - all this can be done with most mobile operators via USSD commands, such as: *100#, *135#, *105*5# and thousands of others.

When accessing the USSD service, the user may encounter the following error: “Connection problems or incorrect MMI code.” In such a situation, you must try to send the request again, making sure that it is correct. If the request for data or the command fails again, you will need to troubleshoot the connection.

You can see an error about an incorrect MMI code on Android, but it makes no difference which mobile operator used: Beeline, MTS, Megafon or any other. One of the methods described below should help you get rid of the error.

Invalid MMI code due to a bug in Android

Google is actively bringing Android to perfection, but this does not prevent various bugs from appearing, especially after smartphone developers introduce their own services, shells and user installation of third-party applications. As a result, an MMI error may appear due to bugs in the system; in such a situation, it is easy to fix:

These actions allow you to “reboot” the networks, since in “Airplane Mode” they are disabled. If the method does not produce results, you can also try restarting your smartphone.

MMI connection problems caused by cellular communications

Often the error “Connection problems or incorrect MMI code” occurs due to a problem with the SIM card or cellular connection. Remove the card from the smartphone and inspect it for damage, as well as for dirty contacts, wipe them if necessary. Also pay attention to the contact pad on the smartphone itself, and clean it if necessary. Next, replace the SIM card and try sending the USSD request again.

If clearing the SIM card contacts did not solve the problem, you can try setting the network type to a fixed one. It is possible that the problem is due to poor communication and constant signal loss cellular communications. In such a situation, on your Android smartphone you need to go to:

“Settings” - “More” - “Wireless networks” - “Mobile networks” - “Network type”

Select one of the available network types instead of the default one. For example, if the smartphone communicates with the operator via LTE, set it to 2G or 3G.

Important: Try accessing the USSD service from all types of networks.

As a last resort, you can try to solve the problem by replacing the SIM card by contacting a mobile phone store.

Additional ways to resolve MMI errors on Android

If none of the above methods help, you can try returning your smartphone to the state it was in before the error occurred. For example, if in recent days there have been changes to options on the device or applications have been installed, you should remove all new items and set the parameters to their previous values.

Another method that often helps to get rid of an error with an incorrect MMI code is to send a potentially erroneous request. It is recommended to send the command “*100#,” instead of the “*100#” request, that is, with a comma at the end. To place a comma on your smartphone keyboard when dialing a number, you need to hold down the asterisk.

If the error does not disappear after trying to fix it using all the methods described above, you can try resetting the phone to factory settings or completely resetting it. Please note that in this case some data may be irretrievably lost.