Verizon HTC One M8 on AT&T - Call / Text OK but not Data. How can I fix this?


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Verizon HTC One M8 on AT&T - Call / Text OK but not Data

So, my wife was up for a new phone, and we were looking to switch from Verizon to AT&T because of company discount, and coverage in places we frequent the most. Well, we went to AT&T last night, and while my wife is the proud owner of a sleek new S6, I now have an HTC One M8 that will only call and text, no data.

My phone should have been factory unlocked, but after putting in the AT&T sim, the first thing that comes up is a notification:

Non Verizon Sim: This SIM card is from an unknown source. (Note, this stays at the top in the notification bar, but does not show up when I drop down or bring up any options to make any changes or anything).

The AT&T reps in the store changed the APN settings, which I then verified when I got home against several sources on the internet... still not data. So then I got a couple of apps that are similar to the LTEonoff HTC Thunderbolt app and switched to various GSM settings, still no dice.

Android 5.01.

I understand I'll likely not have access to LTE, only HSPA+ (which I didn't know until researching last night because AT&T surely didn't tell me that) but that will do for now if I can just get it up and running.

Any help is greatly appreciated.


Mar 7, 2011
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Re: Verizon HTC One M8 on AT&T - Call / Text OK but not Data

Had a similar issue with the phone I simply changed the apn, and then restarted the phone and I was able to get data.
I'm using the VZW M8 on Cricket


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Oct 13, 2014
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Re: Verizon HTC One M8 on AT&T - Call / Text OK but not Data. How can I fix this?

Thanks to all who contributed. Here's mine:
I had similar problems.

The stats:
• HTC One (M8) | Unlocked (bought used in the US) | but still branded Verizon (welcome screen, etc.)
• Tried to use a SIM in PERU, from movistar (Telefonica).
• I had a phone connection, but NO DATA connection.
• And messages: “Non Verizon SIM” “This SIM card is from an unknown source.”
• And a symbol on the status bar: the SIM with a ?

For hours I read threads, and tried stuff. I was about 30 minutes away from rooting the phone.
Then a simple fix (to get DATA. To rid myself of the error messages -- I'll see if I want to worry about after all these wasted hours)!

Here's what I did -- it might work for you, even in other countries and with other providers.

● Settings | Mobile Data | Network Settings | Preferred Network [3 options:]
[1] LTE Mode
[2] LTE/Legacy 3GPP Mode
[3] Global Mode✔ ➔ This was automatically selected, and with that I could make phone calls. ✘

● Settings | Mobile Data | Network Settings: GSM/UMTS Options | Access Point Names | Click the three dots ••• | New APN.
• Then enter the numbers and names that you get from your provider of your data plan. In my case this was movistar. Google it, call them, whatever.
• I give you the example of movistar, but even for another provider, this can alert you to the intricacies of setting this correctly, and being creative and trying out different settings!:

Name = Movistar Internet
Username = movistar@datos
Password = movistar
MCC [country code] = 716 [the phone did this automatically]
MNC [código de red] = 06 [the phone did this automatically] [= Network Code]
Authentication Type = PAP
APN Type = the instructions by Movistar* had me select between: Internet + MMS | Internet | MMS
BUT: There was nothing to select on my phone, but a window opened to type something in!
● First try: I typed in the word: Internet ➔ This did not work, i.e., I did not get a data connection.
● Second try: Movistar, in their instructions for another phone,** told me to select Default. So, I did nothing and simply left this type-text field blank = “Not set” (or rather, erased my previous typing of Internet). ➔ This did work and gave me a data connection. And I even saw in the status bar 4G!
Finally, click the three dots ••• | Select Save!
This did the trick.

● There is one more issue, that I read people could not make work.
Settings | Network Settings | Network Preference | [It gives me a window to fill out:] Add Network: Enter Network Code (Format: MCCMNC) |
MCC [country code] = 716 [Peru]
MNC [netword code] = 06
Doing this, the phone stubbornly refuses to accept this. Instead, it tells me, “Your network preference list is full (0), please remove one from the list before adding new one.” Well, it tells me I have zero (0) network preferences, but my list if "full".... Go figure.
I could not make this work and and set my Network Preferences. However, I have data (G4 LTE), and phone service, and setting Network Preferences might not be necessary at all, so no loss.

In summary: The problem got fixed by playing with the APN settings, trying out different settings that the provider recommends for different phone models and brands.

Hope this helps someone!

*< Cómo configurar tu celular para navegar por Internet | Samsung Galaxy Mini (S5570) | Soporte Movistar Peru >
**< Cómo configurar tu celular para navegar por Internet | Huawei Ascend Y300 | Soporte Movistar Peru >

artan gjoni

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Aug 21, 2015
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Re: Verizon HTC One M8 on AT&T - Call / Text OK but not Data. How can I fix this?

And messages: “Non Verizon SIM” “This SIM card is from an unknown source.” how i remove notification for status bar in htc one m8 6525lvw.

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