Unlocking AT&T 640, SIM card question

tpapictures

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I've got my two 640s being unlocked for me by my dad in the States who will be coming to visit in a few days. I totally understand the whole process of unlocking, we just did his, but he brought up an interesting point about how when he brings them in his bag a TSA official could decide on a random spot check whim to ask for them to be turned on. So, I'm thinking, we unlock them before they leave. But then aren't you supposed to unlock by removing the AT&T SIM and then enter the unlock code with your SIM plugged in? Obviously that won't work, I'm not there. So in that case can we leave them unlocked, just take the AT&T SIM out? If they do in fact need to be turned on before being unlocked, will that cause problems with unlocking them when they get here? Or do you really have to have your SIM card in the VERY first time the phones are turned on?

Thanks, hope that's clear.
 

oditius

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So you got the unlock code from AT&T? If so just have dad buy a TMobile sim card from ebay for around $3. When it comes in, put it in one of them, start it up and unlock the phone. Then do the same for the other. If there is no time for that, then just take out the sim card and toss them in the trash. I started mine with no sim installed. Guess I was just curious. No problem, when they sent me the code (Which only took a day) I just popped in my TMO card and when it started it asked for a unlock code. The trick is not to have it registered with AT&T and you can't do that without a AT&T sim card installed, or WiFi running.,
 

pankaj981

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Have them remove the AT&T SIM card and they can turn it ON without AT&T denying the unlock. If they already have the unlock code for those devices (but not used them) then it really doesn't matter if the SIM is inserted or not.

Alternatively they can also unlock the phone without a non-AT&T sim. All your father needs to do is dial ##7820# and enter the unlock code.
 

RumoredNow

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You don't need a SIM inserted... Your father should remove the SIMs from both phones.

Have him dial ##7820# and it will take him to the screen to enter the unlock code.
 

tpapictures

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Thanks, guys...Just wanted to say from the get-go that I have already had the two AT&T SIM cards thrown out. They're gone.
So you got the unlock code from AT&T?
Well, I've asked for them so I'll get them in a couple of days.
If they already have the unlock code for those devices (but not used them) then it really doesn't matter if the SIM is inserted or not.
Ok, I was under the impression that if the phone was turned on with the AT&T SIM inserted, then it did matter because the phone would become registered as a pay as you go phone.
Alternatively they can also unlock the phone without a non-AT&T sim. All your father needs to do is dial ##7820# and enter the unlock code.
Ok, so they can take the phones as they are with no SIM in them, and when the unlock codes arrive in a couple of days, he can follow the exact same steps to turn on the phone with NO SIM in there and punch in the code because there is no card in it to trigger the unlock code screen appearing on its own. Is that it basically?

So, this phone CAN be unlocked, no problem, with no SIM inserted whatsoever. You just turn it on and punch in the code to have the unlock screen come up and then unlock it even with no SIM inserted. Then when it approves and asks you to accept the license agreement, they just turn it off and when it gets here I put my SIM card in. So even if someone asks to have it turned on or TURNS it on themselves on the way at the airport, it's already unlocked so turning it on won't ruin anything. I was just under the impression for some reason that your actual SIM needed to be in there to register the unlocking somehow.

I imagine WiFi has nothing to do with this then?
 

oditius

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Thanks, guys...Just wanted to say from the get-go that I have already had the two AT&T SIM cards thrown out. They're gone.

That is good...

Well, I've asked for them so I'll get them in a couple of days.

Hopefully you should have it by now. I have seen it in a day, sometimes in 3 max.

Ok, I was under the impression that if the phone was turned on with the AT&T SIM inserted, then it did matter because the phone would become registered as a pay as you go phone.

You should take the sim card out before turning on the phone. After that is doesn't matter.

Ok, so they can take the phones as they are with no SIM in them, and when the unlock codes arrive in a couple of days, he can follow the exact same steps to turn on the phone with NO SIM in there and punch in the code because there is no card in it to trigger the unlock code screen appearing on its own. Is that it basically?

Right, you don't need the other sim card (forgot about the code) Since I do have a TMO card, I just use that.

So, this phone CAN be unlocked, no problem, with no SIM inserted whatsoever. You just turn it on and punch in the code to have the unlock screen come up and then unlock it even with no SIM inserted. Then when it approves and asks you to accept the license agreement, they just turn it off and when it gets here I put my SIM card in. So even if someone asks to have it turned on or TURNS it on themselves on the way at the airport, it's already unlocked so turning it on won't ruin anything. I was just under the impression for some reason that your actual SIM needed to be in there to register the unlocking somehow.

I imagine WiFi has nothing to do with this then?

WiFi isn't a problem as long as you don't register it on there. But generally ones the request is in, it is just a matter of time. And unless he is leaving today, this is probably moot point. You should get the code soon. Good luck and have fun.
 

tpapictures

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WiFi isn't a problem as long as you don't register it on there.
Sorry, not sure what you mean "register". You mean as long as I don't sign in ever to WiFi before my SIM card goes in? If it's unlocked and then WiFi is turned on (not that I would, but if I did) why would it matter?
 

RumoredNow

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Ok, so they can take the phones as they are with no SIM in them, and when the unlock codes arrive in a couple of days, he can follow the exact same steps to turn on the phone with NO SIM in there and punch in the code because there is no card in it to trigger the unlock code screen appearing on its own. Is that it basically?

So, this phone CAN be unlocked, no problem, with no SIM inserted whatsoever. You just turn it on and punch in the code to have the unlock screen come up and then unlock it even with no SIM inserted. Then when it approves and asks you to accept the license agreement, they just turn it off and when it gets here I put my SIM card in. So even if someone asks to have it turned on or TURNS it on themselves on the way at the airport, it's already unlocked so turning it on won't ruin anything. I was just under the impression for some reason that your actual SIM needed to be in there to register the unlocking somehow.

I imagine WiFi has nothing to do with this then?

Correct, the ##7820# hash code is independent of SIM or WiFi.

If I remember correctly, it can even be done before the phone is set up by tapping the "emergency call" option in the no SIM warning box. :cool:

Putting in a "foreign" SIM is just the easiest way, but the hash code "back door" has been used by many with 100% success.
 

coolj40041

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TSA doesn't care if you have a sim card or not. Just take out the att sim card, if one is still in, and leave it empty. Then when the error message comes up, hit "close" and either the start screen or a startup configuration screen comes up (if you haven't already set your phone up with an MS ID). TSA just wants to make sure it's a real phone that turns on like normal phones do, and not some dummy trigger device.

"Suck gas evildoers!"
 

tpapictures

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TSA doesn't care if you have a sim card or not. Just take out the att sim card, if one is still in, and leave it empty. Then when the error message comes up, hit "close" and either the start screen or a startup configuration screen comes up (if you haven't already set your phone up with an MS ID). TSA just wants to make sure it's a real phone that turns on like normal phones do, and not some dummy trigger device.
Ok, so they're not likely to look at it and say, "why do you travel with an unactivated phone?". Things have been a little tense in airports everywhere lately.
Is there by any chance a period of time within which to use an unlock code once it's sent to you?
 
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mggm100

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Is there by any chance a period of time within which to use an unlock code once it's sent to you?

I recently received an unlock code for my AT&T Lumia 1020. I won't need to insert an overseas SIM for few months, so I asked AT&T support if there is a time limit to use the code. They said there is no time limit to use the unlock code.

Now this thread has me wondering if I can key in the code now and continue using my AT&T SIM.
 
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tpapictures

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I recently received an unlock code for my AT&T Lumia 1020. I won't need insert an overseas SIM for few months, so I asked AT&T support if there is a time limit to use the code. They said there is no time limit to use the unlock code.
Now that you mention it, they don't say in the instructions that you have a time frame within which to unlock your phone and I'm guessing (though I don't know) that the unlock code is unique to each IMEI and that it isn't some number they generate for you that has to be verified by having the phone connect.
Well, then, knowing what they told you, since the ATT SIMs are already chucked, I think I'll just have my dad turn on the phones and let them set up automatically with no internet, no SIM, no MS account, and with the generic ATT start screen default apps (IF they even ask him to turn it on) and when I get them here I'll put my SIM in it, unlock, and hard reset them to start the set-up process again. That sound like it will work?
 

pankaj981

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I've taken multiple phones when I travel to India. My primary phone stays with me all others go in my check-in luggage. Just have them put the phones in check-in and they should be fine.

Also unlock codes are permanent.
 
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