OxygenOS OnePlus 6T won't start after android 9 downgrade

  1. Xplos
    Cupcake Dec 27, 2019

    Xplos , Dec 27, 2019 :
    I was having isssues with the android 10 beta and I could not recieve mms messages. This got annoying so I downgraded back to android 9. When I downgraded and the phone went to reboot and turned off, nothing happened and my phone has not been able to start up. I was at 100% battery and I tried holding the power button for 20 seconds, holding the power button with the upper volume button for 20 seconds and nothing is working. What should I do?

  2. Q1555176722523
    Froyo Dec 27, 2019

    Q1555176722523 , Dec 27, 2019 :
    I was under the impression you could not roll back an update because of exactly what happened to you, sounds like you bricked your phone.
    If there is a solution to this I would like to know how because I would like to roll back my update also, 10.3 is a piece of garbage.
    My apologies for being so blunt and truthful.

    SPlusOneC likes this.
  3. Xplos
    Cupcake Dec 27, 2019

    Xplos , Dec 27, 2019 :
    Thanks for being honest. What do you suggest I do now?

  4. M1582135587056
    Cupcake Feb 19, 2020

    M1582135587056 , Feb 19, 2020 :
    same issue here I would like to downgrade my phone to 9 even downloaded the package from Google but can't proceed further as it won't show the file in local upgrade...

  5. Kytharsis
    Nougat Feb 19, 2020

    Kytharsis , Feb 19, 2020 :
    You have to remove the ".jar" extension.

    Caomhin, DrJMun and drl431 like this.
  6. M1582135587056
    Cupcake Feb 20, 2020