Modern mobile phones have a number of advantages over their older counterparts. This is the ability to control touch, and the installation of various applications. However, these devices are still telephones - tools for making calls. They often contain their own errors related to the GSM module. One of the most common is the message about connection problems or incorrect MMI code when working with a SIM card.

general information

To understand the problem, you need to understand what the abbreviation MMI means. It is formed from the phrase man-machine interface, which translated from English means "man-machine interface". The codes of this interface are responsible for the correct recognition of USSD service requests.

In turn, USSD is unstructured additional service data that provides an interactive part of human-device interaction. This is an SMS-like algorithm with one significant difference: if the first serves for communication between the subscriber and the operator or by the phone itself, then the second provides the exchange text messages between users cellular communication... Due to the fact that modern GSM networks are not sharpened for letter commands, asterisks and hash marks are still used to enter them.

MMI codes are sometimes called service codes, they are used to perform the following operations:

• Checking the current account balance. All modern cellular operators, such as Tele2 or MTS, use this very mechanism.
• Balance top-ups using serial numbers scratch cards.
• Management additional services tariff.
• Transition to new tariff and much more.

Reasons for the error

The most common reason for an MMI error is an inattentively typed service code. To fix this, you need to send the same request again. No one is immune to mistakes, and the touch keyboard can still occasionally fail.

This most often happens when the user enters the code with wet hands, and the screen of his phone does not support operation. in high humidity conditions... Then various problems may arise - phantom clicks, errors in recognition of the tapa area by the sensor, etc. Few know what to do if the MMI code is incorrect on Android for no apparent reason.

The source of the problem may be:

• SIM card error.
• Incorrect autodetection mobile operator by the phone itself.
• Invalid network type.
• Conflicting phone settings.
• Interruptions in communication on the part of the operator or insufficient coverage in a specific location.
• Third-party applications interfering with business needs.

Before fixing each of the problems, you need to understand them in detail. There are many solutions, the choice of which depends on the nature of the problem.

SIM card problems

Subscribers often find themselves in this situation. mobile communications who have not changed their SIM cards for a long time. The phenomenon is associated with mechanical and physical wear of the chip in the card. To exclude it, you need to rearrange the questionable SIM card to another device and enter the same code that generated the error. If everything happens again, the card needs to be replaced.

It is also necessary to visually inspect the contact surface of the SIM card. Failures can be caused not only by obvious defects - scratches, delamination from the substrate or visible cracks. If the contacts are darkened or on them whole lines of oxides appeared- this can be eliminated. Use a simple eraser to gently rub the shiny yellow finish. In this case, you should be careful not to overdo it - you can damage the tracks or make a crack.

After that, the card is inserted into the phone and verified. It is highly likely that messages like "invalid session code" will no longer appear. If this does not happen and the error continues to occur, the SIM card will have to be replaced. In the salons of cellular communication, representatives of the operator allow you to save familiar number and not to renegotiate the contract.

Network and operator settings

The coverage of mobile networks in some parts of even large cities leaves much to be desired, despite their widespread use. So, for Megaphone connection problems or incorrect MMI code are not uncommon... Beeline also does not have a flawless connection. However, operators usually fix network problems fairly quickly.

In order to rule out error on the part of the cellular service provider, you can use the following simple methods:

If none of the methods helped, then the module is working properly. It is worth going the other way to check the connection.

In some models Samsung phones invalid code MMI can be removed in an unconventional way. When typing a service code, you need to add a comma to it. Judging by the reviews, this method has helped many owners of Korean-made smartphones.

Phone settings conflict

Smartphones are tuned to run continuously for a long time. They can, periodically recharged, not turn off for months. During this period, information is written to the internal memory of the device, read from there, data is also exchanged between applications and the Internet. May suffer because of this RAM- it is full of fragmentary information about the operations performed until the processor has prepared new ones.

If an error occurs when sending service requests to the operator, you need to perform the following actions:

• Restart your phone. A universal tool for correcting most minor errors. A rebooted system always works better than an overloaded system with temporary files and data scraps.
• Reset the settings after saving all important information from internal memory phone and installed applications using the backup utility.
• Reflash the device by installing a more recent version of the stock software or one of the many custom ones.

When choosing a firmware, you should go to one of the specialized resources, for example, w3bsit3-dns.com, and ask if there is CyanogenMod or LineageOS there. These are functional firmware versions based on pure Android without established promotional offers under an affiliate program or service utilities from the manufacturer. Many users call them great alternatives to that set. software tools, which is imposed upon the purchase of the device.

You should be wary of those custom designs that, although they look attractive, are not fully supported by the phone. Sometimes after downloading the ROM file and going through all the steps ready system on models of the Chinese company Xiaomi didn't connect to the internet via Wi-Fi. At the same time, smartphones issued a similar message - "Invalid device ID: null". To solve this problem, it was required to do a full wipe - delete, clear and reformat the entire internal memory of the device, and only after that - flash it.

Application problems

V Play Market there are several million programs for Android devices. Not all of them are equally safe and beneficial. Even if the developer is pre-certified v Google and created an application that meets all the guidelines and requirements, he can over time update its functionality so that important system components will be affected. In older Samsung models, a connection problem or an invalid MMI code could occur even due to the fact that cleaning utilities were found in the system. Memory managers and pseudo-optimizers could also be the cause.

You can make sure that the reason really lies in some application when you clean boot the device or, as the developers themselves call it, when starting safe mode. To do this, just start the end of the session by holding down the power button. When the pop-up menu appears, you do not need to touch the disable option, but hold it down. After that, another menu will be displayed on the screen, which will ask you to confirm the reboot.

After switching on, the device will start without loading background processes, special drivers or services - it will be a black window with no background with the words “ Safe mode»At the bottom of the screen. Then you need to enter the code that caused the problem and check its execution.

If a communication device was bought "gray" or from abroad, programs could be installed on it that openly use the connection ports allocated for USSD requests for various purposes. One of these programs can be called VLock (VeLok) - a tool for reading and storing electronic locks using an NFC telephone chip for Western security systems and intercoms.

Another potential pest is the advanced mobile photographer tool FX Camera. V license agreement and the list of permissions requiring confirmation, it does not contain any mention of access to mobile or wireless networks.

Sometimes such applications can only be eliminated by flashing. However, there are special tools for deleting and cleaning that can quickly remove even programs deeply embedded in the system from the internal memory.

Change of location

Some smartphones give this error due to problems in the system, constant changes in the owner's location and frequent crossing of state borders. At the same time, even a flashing, which seemingly solves any difficulties, does not help. The solution to the problem is quite trivial, but it is not obvious for every user.

In the settings of parameters for incoming and outgoing calls, there is a "Location" section. Among other settings, there is an item that is almost always marked with a tick - "Country code by default." If you turn it off, before the dialing number will not be prefixed with +7, +4 or +3. Service signals will start to pass and the smartphone will work normally.

The opposite situation is also known, when it was the automatic recognition of geolocation and the addition of regional prefixes that helped. In any case, upon occurrence technical problems you should always use different options for solving them and be ready for experiments.

Sometimes smartphone owners are faced with what is on the screen mobile device a message appears in English "Connection problem or invalid MMI code" or in Russian "Connection problem or invalid MMI code" on Xiaomi. This situation occurs when 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 is solved in several ways, which we will tell you about.

Change settings and restart your phone

If an error occurs on the display, it is recommended to restart the smartphone. If, after this action, it is not possible to generate a USSD request again, 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, deactivate the mode and check if the error remains.

Safe Mode Activation

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

If information about the 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.

Signal level check

If the signal of the mobile operator 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 on the display of information about the connected network: then 3G, then EDGE, etc. In this case, you can try to go to "Settings" - "SIM cards and mobile networks".

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

Roaming

It so happens that a Xiaomi smartphone in another country is tuned to the coverage of a local operator, as a result of which it becomes impossible to send requests to its network. You can use the above sequence of actions and select the item " Mobile networks". Instead of automatic network selection, you should choose your operator. If this does not help, then it remains to contact the support service to clarify the issue.

Much less common is the situation when the message "Invalid MMI code" on Xiaomi becomes a consequence of the inoperability of the SIM card. Only its replacement will help here.

Sometimes, when using an Android smartphone or tablet, an error occurs: “Connection problems or incorrect MMI code”. In English, this error looks like this: "Connection problem or invalid MMI code".

Usually, given error occurs when trying to send a request to a telecom operator, for example, when trying to find out the amount of funds on the account.

The MMI code allows the service provider to identify the user when performing various services. Moreover, an error related to the MMI code occurs on devices regardless of the brand and operator. The reasons for the error can be different, it can be a malfunction of the telecom operator, and incorrect device settings, and even the work of recently installed applications.

How to get rid of the error "Connection problems or incorrect MMI code"

Depending on the reason, there are several ways to resolve the error. It is best to start solving the error with the simplest ways.

Despite its simplicity, you should not ignore this way, because rebooting the device can really help solve various errors, including the error "Connection problems or incorrect MMI code".

2) Changing the request code.

Another easy way to get rid of the error adding a comma to the query... For example, in order to find out the amount of funds in the account, you just need to add a comma to the usual request.

It is this method that helps most users get rid of this error. To add a comma, you need to hold ∗ .

3) Removing recently installed applications.

If previous ways did not help you, perhaps uninstalling recently installed applications will help you. To check if an application is causing the error, boot your device in safe mode... To enter safe mode, you need to turn off the device and simultaneously press the power button and the "Volume -" button (depending on the brand of the device, the method of entering safe mode may differ). Upon successful transition to safe mode, the system will notify you of this. Check if the error appears when the device is in safe mode. If the error disappears, then the problem is in one of the recently installed applications and it must be removed.

USSD services are long accepted standards for communication between subscribers. cellular networks with service servers. Sending USSD messages is reminiscent of communicating with bots in Telegram and other services where they have become widespread. 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 phone users do not even imagine what a USSD interaction service is, while regularly using it. Balance check, change tariff plan, connection of services - all this can be done with most mobile operators through USSD commands, such as: * 100 #, * 135 #, * 105 * 5 # and thousands of others.

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

You can see an error about an incorrect MMI code on Android, and it makes no difference which mobile operator used: Beeline, MTS, Megafon or any other. One of the methods described below should help to 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 save it from the appearance of various bugs, especially after the developers of smartphones have introduced their own services, shells and installation by the user 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 it:

These actions allow you to "reboot the networks", since they are disabled in "Airplane mode". If the method fails, you can also try restarting your smartphone.

MMI connection problems due to cellular communication

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

If cleaning the contacts of the SIM card did not help to solve the problem, you can try to set the fixed network type. It is possible that the problem is due to bad connection and constant loss of cellular signal. In such a situation, on an 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. For example, if the smartphone communicates with the operator via LTE, put 2G or 3G.

Important: Try to access 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 cellular salon.

Additional ways to fix the MMI error on Android

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

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

If the error persists after trying to fix it using all the methods described above, you can try resetting the phone to factory settings or completely resetting it to zero. Please note that in this case, some data may be irretrievably lost.

Everyone who has a mobile android phone colliding with the pop-up window while typing USSD command: "Invalid MMI code". There are different interpretations of the message, but they have in common - the MMI code. What does the mysterious message mean: connection problems or incorrect MMI Tele2 code?

MMI - linking code between USSD request subscriber and service application of the operator. It is sometimes formed incorrectly and an error appears, which can be seen on the screen in the form of a corresponding message.

Causes

A problem in the formation of the code occurs for various reasons: a breakdown of the gadget, inattention of the user when entering the USSD number, breakdown on the server of the service company. Fix the first two points according to the strength of the user himself, and we will analyze them further.

What to do, connection problems or incorrect mmi Tele2 code on Android

There are many ways to overcome the problem, at least one, but it will work. Most often, the connection problem occurs due to the subscriber's own inattention and the input of extra invalid characters in the request or invalid commands.

Send the USSD command again

The most common command among users is checking the balance by * 100 #. Did the phrase "faulty MMI Tele2 code" appear as a result of checking the account? You need to check the connection, if everything is in order with it, then send the request of interest several times with an interval of 5 minutes. If this does not help, you should contact the operator to exclude the option with a problem with the service company.

Turn airplane mode on and off

A useful key in every Android is flight mode. When enabled, all communication options on the device are disabled. After disabling the mode, you need to enter the USSD request of interest again.

If the operation of the gadget is interfered with by a failure in its system, then it is necessary to reboot or turn off and on, then check for an error.

Network type changes

Today there are network types: 4G, 3G, 2G. You need to try switching to a different type in order to eliminate the error. In the settings, you need to find the "Mobile networks" section and in the "Network mode" select a different type, different from the current one. Then type USSD, if there is no error, then you can return the previous type of network.

Operator network check

It happens that the device is configured by an unnecessary operator. To check the settings, you need to go to "Mobile networks", to the "Network operators" section and select the required telephone company. Manipulation will help, especially when roaming is available.

Additional downloaded applications often interfere with the normal operation of the phone. To disable all applications and keep working only system settings you need to install "Safe Mode". He will allow you to find out if they interfere third party programs the functioning of the smartphone.

To turn on the mode in most phones, you need to hold your finger on the "Power off" button for a few seconds. Next, a sign will appear showing the transition to safe mode or the smartphone will immediately turn off. When turned on, the bottom of the screen will be marked "Safe Mode". In the mode, you need to type the command of interest and see if the smartphone works better.

To reset the mode, the phone needs to be rebooted.

SIM problems

A faulty SIM card can contribute to the appearance of an MMI code error. The card may be old, worn out, or improperly cut. Only replacing it with a new one will help. The service is provided free of charge in any service center operator.

If the listed methods do not help to fix the problem, all that remains is to contact the telecom operator for help, perhaps the breakdown is not with you, but by the service organization.