Why Xiaomi does not send SMS: expert guide

When you stop sending or receiving text messages on a Xiaomi smartphone, it can often be a bit of a surprise. This can be critical if you expect a confirmation code from a bank or important information from an employer. Most of the time, the problem is not a hardware breakdown, but a software failure or misconfiguration of settings that are easy to fix yourself.

Modern MIUI devices have a complex power management and traffic filtering system that sometimes works too aggressively, which can block a standard Messages application or communication module from working as a background process that requires no resources. Understanding the logic of Xiaomi’s security system is the first step to successfully solving an SMS problem.

In this article, we will discuss in detail all possible causes of problems, from the banal lack of funds in the account to complex failures in network registrations. You will get a step-by-step algorithm of actions that will help return full functionality to your device without contacting the service center.

Status check SIM-maps and balances

The first thing to do if messages don't leave is to make sure that there are physical connections and funds in the account, and operators can block outbound traffic with zero balance or debt, even if incoming calls and the Internet are working. Check the subscription status through your carrier’s app or USSD-team.

Sometimes the problem lies in the SIM card slot itself or in the contacts. If you use a two-symbol Redmi or POCO, try to move the cards in places, which will eliminate the malfunction of a particular slot or the oxidation of contacts on the card itself.

• 📱 Make sure that SIM-The card is active and not blocked by the operator for lack of activity.
• 💰 Check if the limit of sent messages is exhausted if you have a tariff for each SMS.
• 🔄 Remove the SIM card, wipe the contacts with a soft cloth and paste back before clicking.
• 📶 Make sure the status bar shows the network icon (2G, 3G, 4G), Not the net».

It is worth noting that the old SIM-maps that were used more 5-7 In the years that have passed, they may have physical damage to the chip or may not support the current encryption standards used by operators, in which case, changing the card in the communication salon will solve the problem instantly.

Message center and network settings

One of the most common technical reasons why you don’t send an SMS to Xiaomi is that you don’t have a Message Center Number (SMSC) that is responsible for routing your messages through the operator’s server, and if the number is downed or empty, the message stays in the “Send” status indefinitely.

To check and change this setting, open the standard Messages app, click three dots in the corner of the screen and select Settings. Next, look for “Additional” or “Settings”. SIM-This is where the message center number is written, which should correspond to your operator.

If the phone tries to send a message via VoLTE or in 5G mode, and the coverage in your zone is unstable, there may be failures. Switching to 3G/2G or Auto mode often helps stabilize the connection.

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If you don’t know the exact SMSC number, try resetting the network settings to factory settings – the system often pulls up the correct settings from the operator itself.

Failures in the “Messages” application

Software errors in the messaging app itself are another common cause of problems: the app cache can overflow or get corrupted, causing the send function to malfunction, and in MIUI, data cleanup often solves these problems.

To do this, go to Settings → Apps → All apps. Find Messages (or the app you use, like Google Messages) in the list. Click on it, select Memory and then Clear (or Delete Data) and don’t worry, your text messages won’t be deleted, only the program settings will be reset.

If the cleanup didn't work, try changing the default app. In the settings, look for "Default Apps" and select another SMS messenger if installed, which will let you know if the problem is in a particular software or system as a whole.

In some cases, removing app updates completely helps if the problem has occurred after a recent update: Go to the app card in the settings, click on the three dots in the top corner and select "Delete updates." After that, the phone will return to the factory version of the app.

The influence of blockers and antiviruses

Xiaomi smartphones have a powerful security tool that includes antivirus and blocker, and aggressive settings can perceive sending SMS as suspicious activity, especially if you send a lot of messages in a short time, or block short service numbers.

Check the blacklist and blocker settings. Go to the Security → Antispam app. Make sure the number you're trying to send the message to or the service itself isn't on the blocked list. Also check the permissions for the message app.

• 🛡️ Go to Settings. → Annexes → Permits and make sure that the “Messages” have access to the SMS phone.
• 🚫 Check the Blacklist for Accidental Important Numbers.
• 🔋 Turn off Energy Savings for the message app so the system doesn’t kill its process.
• 📲 If you have a third-party antivirus installed (Kaspersky, Dr.Web), try temporarily disabling its protection.

⚠️ Warning: Enabling Do Not Disturb or Flight Mode may also block sending messages.Make sure these features are disabled in the notification curtain.

Problems with networking and mode switching

Sometimes the phone gets stuck on a particular type of network or base station that can’t handle a request to send an SMS. This often happens when you move between coverage areas or switch between 4G and 3G. Network reset helps the device re-register on the carrier’s network.

To do this, go to the Settings. → SIM-Select the problematic SIM card and find the "Network Type" option. Try to force the switch to "Preferred" 3G» (or 2G), send a message and then return the settings back, and this action initiates re-registration on the network.

Another effective method is to reset APN (Access Points), although it is more about the Internet, but sometimes affects the operation of service messages. In the mobile network menu, find “APNs”, click on the menu at the bottom and select “Reset”.

System Errors and Software Update

Global failures in the Android operating system or the MIUI shell can cause communication module conflicts. If the problem appeared immediately after the firmware update, it can be a bug of the new version.

Check for system updates. Go to Settings → About Phone and click on MIUI. If a new update is available, install it. Often, developers quickly release hot fixes to fix critical communication errors.

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If the problem occurs after a firmware update, try resetting the network settings or performing a full reset (with data saved) as old configuration files may conflict with the new system.

In extreme cases, if nothing works, you can reset all settings to factory. This action will delete all your data, contacts and applications, so be sure to back up before starting the procedure. Reset is made through the menu "Advanced settings" → "Recovery and reset".

⚠️ Note: When resetting to factory settings, make sure you remember the password from your Google account (Mi Account), otherwise after the reboot, the phone may request authorization, and without data you will not be able to use it.