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New Member

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11 Messages

Sun, Aug 8, 2021 7:03 PM

European phone can't register to AT&T: Error GA205

Hi,

my son arrived in the US last Thursday and he wants to activate an AT&T prepaid SIM card.

He get's a text message with error code GA205, stating in the text "the phone you recently tried to activate won't work"

He went to the store again today and when he was in the store, the shop assistant was able to call him on his US number.

But once he was back in his room, he again got the same text message.

What can be wrong?

The phone is a (european) Samsung Galaxy S8

Thanks in advance.


Regards,

Luc

Accepted Solution

Official Solution

sandblaster

ACE - Expert

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59.7K Messages

1 عام مضت

Without checking the supported phone list, I’m pretty sure the problem is his phone is not on ATT’s supported phone list and ATT will no longer activate a phone not on the supported list. 

OttoPylot

ACE - Expert

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18.8K Messages

1 عام مضت

It could be that the IMSI number for a non-domestic phone is not recognized on the AT&T network. It is almost impossible for any carrier to recognize every single IMSI number for all carriers world-wide. The IMSI number is comprised of the MCC, MNC, and the MSIN identity codes.

If that is the problem then I don't think AT&T can change it because I believe the IMSI number may be embedded on Android phones and not on the SIM card. He may just need a new SIM card tho.

New Member

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11 Messages

1 عام مضت

Hi,

thanks for your answer.

Isn't it strange that it worked once in the store?

I'd think this would be a binary problem: either it never works or it always works?

New Member

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11 Messages

1 عام مضت

Furthermore, his European SIM card is working on the AT&T network

OttoPylot

ACE - Expert

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18.8K Messages

1 عام مضت

Did he get a new SIM? It is strange that it worked in the store but not out in the wild. Has he reset the phone? Maybe that's what it needs as well as a new SIM.

OttoPylot

ACE - Expert

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18.8K Messages

1 عام مضت

I missed that it was a prepaid phone. I don't know how that would affect a European Android phone but we do have an Android expert here so maybe he can shed some light.

New Member

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11 Messages

1 عام مضت

He got a new SIM yesterday, but he didn't activate/try it in the store.
When he was "in the wild" and tried to activate it, he got the message "GA205: ... We're sorry, but the phone you recently tried to activate won't work. ..."
So he went to an AT&T shop today and they helped him to activate it, and the shop assistant was able to call him on the new SIM/number.
But when he was back "in the wild" he received the same text message again

New Member

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11 Messages

1 عام مضت

Don't they check this when he is in an AT&T shop specifically for this problem?

sandblaster

ACE - Expert

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59.7K Messages

1 عام مضت

They should.

New Member

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11 Messages

1 عام مضت

Samsung Galaxy S8 is on the supported phone list, but he has the G950F and on the list is G950U
I don't know if that makes a difference

OttoPylot

ACE - Expert

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18.8K Messages

1 عام مضت

That's probably the reason then. 

sandblaster

ACE - Expert

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59.7K Messages

1 عام مضت

The model number does make a difference. His model is not on the list, hence not supported.

New Member

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11 Messages

1 عام مضت

OK,
so he should change provider or phone?

I've chatted with T-Mobile and they check via his IMEI number and according to the, the phone is compatible.

Should I trust them?

OttoPylot

ACE - Expert

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18.8K Messages

1 عام مضت

That's up to you. If you are happy with AT&T, get a new phone. If not, and T-Mo says his phone will work, then switch to them.

New Member

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11 Messages

1 عام مضت

Since he's only in the US for 4 days, we don't have any affinity with either provider yet ;-)
Thanks you very much for your assistance!

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