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How To Fix: Invalid MMI code

Discussion in 'Android Help' started by king845118, Dec 27, 2019.

  1. king845118

    king845118 Lurker
    Thread Starter

    Invaled mmi code

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  2. mikedt

    mikedt 你好

    It means you're sending an MMI code that your carrier network doesn't recognise. MMI codes are used to setup things like call diversion, check account balance, etc. and can be carrier specific. To fix, check with your carrier customer support or website for their correct MMI codes.
    #2 mikedt, Dec 27, 2019
    Last edited: Dec 27, 2019
    MrJavi, Billtunew and ocnbrze like this.
  3. Billtunew

    Billtunew Member

    I do not know a specific way how to fix it, but I found it on Quora, hope it can help you:

    You are getting “Connection problem or invalid MMI code”, this error mainly occurs because of the connection issues & sim card authorization. This issue mostly happens in dual sim smartphones.
    • Switch Off your phone
    • Hold the power button
    • While holding the power button, keep tapping the menu/home button
    • Now, when you see the greetings with a safe mode logo
    • Enter the USSD string you were trying to enter within the dialer and see if it is working or not
    • If it is working, then certainly there is an app that is causing the Invalid MMI Code error on your phone.
    • Restart your phone and remove the recently installed apps.
    This is another simple and effective way to fix the error on the android phone. This can be done by just adding a comma at the end of the prefix code.

    For example, if your prefix code is *123*1#, then you just need to add a comma at the end of the string. Like, *123*1#, will solve the problem.

    Restarting your mobile phone many times sometimes can do the magic. Basically, turn ON your phone and navigate to network settings. Then hold the power and the home button together until your phone turns off. Then again switch it on to get rid of this problem. Maybe this simple exercise helps you out.
    MrJavi and mikedt like this.

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