521 Runs on AT&T 3G Network Without Unlocking

[Ertonimus]

I have about phones with active SIMs in them kicking around my apartment for work so I decided to see what would happen if I put one of the active ATT sims into my 521. I was sort of hoping it would magically unlock... it of course did not and asked for an unlock code. I pressed the Windows button to see what would happen and it brought up a 'Access Point' and asked me to select an AT&T network the it gave me two options for LTE which were 'unavailable' but it had an option for 3G that was available. I clicked it, pressed the back button and it brought me my home screen. I had full data access on the ATT network even though it was saying no SIM installed and I couldn't make calls. Does this make sense or am I right in being surprised that its functioning this way?

 

[peacefulberry]

It may be true, but if it doesn't recognize the SIM, how are you able to make calls? Are you able to make calls? Texts?

 

[Ertonimus]

It may be true, but if it doesn't recognize the SIM, how are you able to make calls? Are you able to make calls? Texts?

Its definitely true as I did it. I can't make calls or texts on the ATT network but I have full data access. Anyone know how that's possible? I would have thought I'd be locked from the network entirely. I have some Verizon SIMs as well. I'm out for the night but will see if it works with them too.

 

[angryGTS]

Any access to APN settings?

 

[Dustin Hodges]

I think this may be a Nokia Thing. Under Extras+Info I noticed "SIM Unlock v1.0.0.5" in the list of enhancements from Nokia. Perhaps, even though the phone itself is locked, Nokia has it partially unlocked for Data Use?

 

[Jnbs]

It may be true, but if it doesn't recognize the SIM, how are you able to make calls? Are you able to make calls? Texts?

Wifi calling and for text whatsapp ot any other alternative

 

[Corepc]

Do you happen to live in a T-Mobile refarmed area, it may be that is how you are on at&t network.
I noticed that my t-mobile sim has at&t apn settings but they are not fully working.

 

[Ertonimus]

Do you happen to live in a T-Mobile refarmed area, it may be that is how you are on at&t network.
I noticed that my t-mobile sim has at&t apn settings but they are not fully working.

I do live in an ATT refarmed area so that may be it. I'm going to pop a Verizon SIM in shortly and see what happens.

 

[peacefulberry]

Wifi calling and for text whatsapp ot any other alternative

Doesn't the carrier have to activate WiFi calling even if you're using WiFi, is it a carrier and phone feature? I've never used it before which is why I'm asking. Also the SIM card has your phone number attached to it. How are you able to use WiFi calling when the phone can't read the SIM like the OP said?

 

[Corepc]

Wifi Calling for 521 will not come until the Firmware update comes on 20th of this month hopefully..

 

[Ertonimus]

Just tried a Verizon and it didn't work. This is the screen that came up when I first put the ATT SIM in. It's the Access Point menu from the settings. I don't think it has anything do with the refarm because I can also view and 'activate' the ATT LTE networks. I can't access a data connection from the LTE networks but that may just be because the 521 doesn't have those bands.

I don't think there's any practical use to this but thought I'd share as it seems interesting.

 

[berrywr]

The Nokia Lumia 521 RM-917 runs on HSDPA 850 / 1700 / 1900 / 2100 which covers both T-Mobile's and AT&T's HSPA bands. I've also read there is a Nokia Sim Unlock v1.0.0.5 setting as well. Given the prices of the 521, it can be assumed that many will outright buy the device thus T-Mobile is then obligated to allow their customers or anyone else for that matter to unlock the device. I'm planning on buying the 925 as my main driver and the 521 and running it on Straight Talk (AT&T) but before someone says why not the 520; simple, the 521 gives me a backup phone with Wi-Fi calling if it becomes necessary to throw a T-Mobile Sim card back into the device. AT&T turned on their HSPA+ in just about every area they had EDGE on 1900. I would like to see T-Mobile work on their coverage more than anything else but I digress. One note, I performed the field test that is on both the 925 and 521 and despite T-Mobile's 4G claims, unless you know for a fact you have LTE, which where I live we don't; the field test revealed true 4G is not available; a point that stunned the kiosk I go to when they swore to me they had it and I said, prove it! I pulled up the field test mode...their jaws dropped...ran all the LTE diagnostics...all goose eggs and said to them, any questions?