If you want to enable T-Mobile voice and data on your AT&T Galaxy Note, you will need to unlock SIM on your AT&T Galaxy Note SGH-i717 first.
Step 1. Dial *#06# in your Dialer.
Step 2. Write down the IMEI number you get.
Step 3. Go to Cellunlocker.net. (You can also use any other cellular unlocking service of your choice. I just used this one since it came up first on Google.)
Step 4. Choose i717 Galaxy Note 4G LTE or the phone you have. It should also work for Rogers/Telus/Bell.
Choose AT&T for carrier.
Enter your IMEI number.
Step 5. You can pay like $24.95 to unlock your phone. You should receive your unlocking code within 5-10 minutes in your e-mail.
Step 6. Reboot your phone after putting T-Mobile SIM card in (or any other SIM card that’s non-AT&T).
Step 7. When your phone reboots, it will ask you for the Network Lock Control Key. Enter the Network key you got in your e-mail and it should unlock your AT&T Galaxy S2.
Now your AT&T Galaxy S2 should be able to use T-Mobile voice and edge speeds for internet. For 3G/4G, you will have to install a T-mobile modem, which is coming next.
Q: I am still not getting any signal on T-Mobile!
A: This guide was written originally for Gingerbread. It’s most likely because you are running ICS. You can install an ICS modem instead to get it working, get it here.
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You will need a rooted Galaxy Note to install all ROM/kernels.
NOTE: If you are a noob, please remember the author of this site is not responsible if you mess up your phone. Make sure you know what you are doing before following any instructions on this site!
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