How To Fix Connection Problem or Invalid MMI Code On Android Device

For Android users sometimes a message saying “Connection problem or invalid mmi code” shows up and can be a frustrating thing to deal with. When the invalid MMI code message is shown, it generally means that calls or text messages can’t be sent until this issue has been fixed. But there are several ways to fix Android connection problem or invalid mmi code that will be explained below.
There are several reasons why the “Connection problem or invalid mmi code” error message appears, the main reason can be because there is issues with the carrier provider or problems with the SIM authentication on the smartphone.
The following are several different methods to fix the connection problem or invalid mmi code on an Android device.

Restart the Android Device
The first way to try to fix an invalid MMI code would be to restart the smartphone. Going to to network settings and then holding the “Power” button and the “Home” button at the same time until the phone turns off and starts vibrating will restart the smartphone.
Another way to fix the Connection Problem or Invalid MMI Code on an Android smartphone would be to add a comma at the end of the Prefix code. When a comma is added, it forces the operation to execute and overlook any error. Below are two different ways that this can be done:
  • If the Prefix code is (*2904*7#), then add a comma at the end, similar to this (*2904*7#,)
  •  You can use the + symbol after * similar to this  (*+2904*7#)

Activating  Radio and Turn on IMS over SMS

  1. Go to the Dial pad
  2. Type in (*#*#4636#*#*) NOTE: No need to press the send button, it will automatically appear the Service mode
  3. Enter Service mode
  4. Select on “Device information” or “Phone information”
  5. Select Run Ping test
  6. Click on the Turn Radio Off button and then the Galaxy will restart
  7. Select reboot

Check Network Settings

  1. Go to “Settings”
  2. Then select “Network Connection”
  3. Followed by “Mobile Networks”
  4. Then, “Network Operators” and select wireless provider during the search
  5. Connect again for another 3-4 attempts before it starts working again




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