How to Fix Connection Problem or Invalid MMI Code: A Step-by-Step Guide

Getting an error message that says “Connection problem or invalid MMI code” on your phone can be frustrating, right? But don’t worry, you can fix it without pulling your hair out. Simply follow a few steps to get your phone working again.

Step by Step Tutorial to Fix Connection Problem or Invalid MMI Code

Before we dive into the steps, let’s understand what we are fixing. MMI code stands for Man-Machine-Interface code. It’s a way for your phone to communicate with your carrier’s network. When there’s a problem, you can’t make calls or send texts. But with these steps, you’ll be back in business in no time.

Step 1: Restart Your Phone

Turn off your phone, wait for a minute, and then turn it back on.

Restarting your phone is like giving it a fresh start. It can fix many small glitches, including the MMI code error. It’s the simplest fix, so always try this first.

Step 2: Check for Network Issues

Make sure you have a good signal and that your carrier isn’t experiencing any outages.

Sometimes, the problem isn’t your phone, but the network. A quick check to ensure there’s no outage in your area can save you a lot of troubleshooting.

Step 3: Enter the Code Correctly

Double-check the MMI code you’re entering and make sure it’s correct.

MMI codes usually start with an asterisk (*) and end with a hash (#). If you miss a character or add an extra space, the code won’t work.

Step 4: Add a Comma at the End of the Code

Try adding a comma (,) at the end of the MMI code.

Adding a comma can force the operation to execute, bypassing any issues. To add a comma, just press and hold the asterisk (*) key.

Step 5: Check for Software Updates

Update your phone to the latest software version.

Software updates often fix bugs, including ones that might be causing your MMI code error. Always keep your phone updated for the best performance.

After completing these steps, your phone should be back to normal, and you can continue using it without any error messages.

Tips to Avoid Connection Problem or Invalid MMI Code

  • Keep your phone’s software up to date to avoid bugs that can cause MMI code errors.
  • If you’re in an area with a weak signal, try moving to a spot with better reception.
  • Avoid using MMI codes during peak hours when the network might be congested.
  • Make sure you’re entering the MMI code exactly as it was given to you, with no extra spaces or characters.
  • If the problem persists, contact your carrier as there might be an issue with your account or SIM card.

Frequently Asked Questions

What is an MMI code?

An MMI code is a special code you enter on your phone’s dialer to access certain features or information from your carrier.

Can I fix the MMI code error myself?

Yes, often you can fix the MMI code error by following a few simple steps, like restarting your phone or checking for software updates.

Why does the MMI code error happen?

The MMI code error can happen for various reasons, such as network issues, incorrect code entry, or software glitches.

Will I lose any data by fixing the MMI code error?

No, fixing the MMI code error doesn’t involve any data loss. It’s a safe process.

What if none of the steps work?

If none of the steps work, reach out to your carrier for further assistance. There might be a more complex issue at play.


  1. Restart your phone.
  2. Check for network issues.
  3. Enter the MMI code correctly.
  4. Add a comma at the end of the code.
  5. Check for software updates.


Dealing with a “Connection problem or invalid MMI code” error can seem daunting, but it’s usually a simple fix. Whether it’s a network issue, a typo, or a software glitch, following the steps outlined in this article should get you back up and running in no time. Remember to keep your phone updated and enter codes carefully to avoid this issue in the future. If the problem persists, don’t hesitate to contact your carrier for help. They’re there to ensure you have a smooth experience with your mobile device. So, next time you face this error, take a deep breath, and remember, you’ve got this.

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