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Level 1: Joiner
Posts: 4
Registered: ‎08-01-2021

Obtain MCK code for my ex-O2 Samsung Galaxy J3 (?)

[ Edited ]

FAO @Martin-O2 

My partner recently gifted me her old Samsung Galaxy J3 (2016), which she used under O2 contract for several years. She is no longer with O2 but we retain details of the legacy account, and obviously can access device data on the J3.

I obtained an EE SIM to put in the J3. Prompted for a “SIM network PUK” I entered the one provided by EE, multiple times (definitely more than three).

When this did not work I contacted O2, who provided me with an “unlatch code”. This suggested the J3 had in fact been locked to O2 all along, although the device gives no explicit sign of this. When prompted again for “SIM network PUK”, I tried the O2-provided code instead, to no avail.

I have now tried two different codes multiple times. Any such action prompts the same ‘unsuccessful attempt’ message, and a notification remains on the phone saying: ”Invalid SIM card. Network locked SIM card inserted”.

The new EE Sim works in another, older Samsung phone, so the card is obviously activated. I do not believe the card itself to be “locked”, rather the Galaxy J3 is not accepting it.

Given my multiple inputs of two different PUK codes, I believe my J3 may be frozen, requiring unlocking at the level of MCK code, or deeper.

My understanding is that such an MCK or “unfreeze” code needs to be obtained by the original (now legacy) provider in liaison with the device manufacturer.

If so, O2, can you please help me to un-freeze my phone?

Thank you, in anticipation.

Level 70: Enigma
Posts: 17,173
Registered: ‎31-03-2010

Re: Obtain MCK code for my ex-O2 Samsung Galaxy J3 (?)

@Martin-O2@LukasB, or @TheresaV can one of you please assist @Mr_A_Stones?


Community Manager
Posts: 1,630
Registered: ‎07-05-2020

Re: Obtain MCK code for my ex-O2 Samsung Galaxy J3 (?)

Hey @Bambino im here to help. @Mr_A_Stones I will send you a private message on here as I will need some personal Information.

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