Do you have to travel and will you need to insert a local SIM card in your Galaxy 3? Do you want to change operator but not the phone? You may need to unlock your phone in order to use it with a different SIM card. Fortunately, there are a couple of ways to do this, even if your carrier doesn't unlock it. Read this guide to learn how.
Steps
Method 1 of 3: Unlock the Phone through your Carrier
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Step 1. Contact your network operator and request an unlock code
In some cases the operator will not provide you with the unlock code until the end of the contract, or until you have passed a specific period under the contract.
- Operators may be more inclined to unlock your phone if you explain that you will need to travel overseas and need to purchase a SIM card once you arrive at your destination.
- If your carrier doesn't give you a code, try one of the other methods described in this guide.
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Step 2. Insert a SIM card from a non-authorized carrier for your phone
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Step 3. Turn on your Samsung phone
You will be prompted for an unlock code.
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Step 4. Enter the unlock code
When you do, your device will start receiving the new carrier's signal. If you have no range, contact the new operator, and check that the area you are in is covered by their signal.
Method 2 of 3: Unlock Your Phone Using a Paid Online Service
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Step 1. Get your phone's IMEI number by typing * # 06 # on the keypad
A screen will appear showing you the number. Make a note of this number for later use.
- Make sure you write the code; it cannot be copied and pasted directly into the space provided;
- You can find the IMEI number printed in a sticker under the phone battery. However, it is not recommended to use that or perhaps the code printed on the package; it could be different from that of the device itself and consequently the unlock code would not work.
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Step 2. Find a paid unlocking service
There are many internet sites that offer unlocking your phone for a fee. Read the reviews and make sure other users were happy with the service. You will need to provide your phone's IMEI number. Note: most of these services operate in a legal gray area, because the unlocking operation is on the verge of legality.
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Step 3. Order an unlock code
Once you have found a reputable site, order your code. Make sure you type in your carrier name, model and IMEI. Don't trust those sites that claim to unlock your phone for free. If they invite you to fill out a questionnaire or join an affiliate program to get your code, this is most likely a scam.
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Step 4. Wait for your unlock code to be delivered to you
Depending on the service you have chosen, you may need to wait a few hours or a few days. You may receive the code via message, email or through a phone call; it really depends on the rules of the site you choose.
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Step 5. Insert the new SIM card
Make sure it's not the old operator's. When prompted to enter the unlock code, use the one you received from the website. Check that you have a field and that the code worked correctly.
Method 3 of 3: Manually Unlock a GSM S3
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Step 1. Make sure your phone is locked
Insert the SIM card for the new network and check if the phone is actually locked. Many S3s are in fact already unlocked by default. Verification saves you time.
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Step 2. Update your phone
Your phone must be running Android 4.1.1 or later for this method to work. You can check the device version by opening the "Settings" and then scrolling to the bottom of the page and selecting "Device Information". Look for "Android Version" to find your version number.
- To update your phone, open Settings and then scroll down to Device Information. In the next menu, select System Updates and then Check for Updates. Your phone will try to update itself automatically.
- Update through your wireless network, since the new SIM has no connection yet.
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Step 3. Make sure your phone is GSM
It is not possible to unlock an S3 operating on a CDMA network.
This method is not guaranteed to work with all versions of S3, but it costs nothing to try
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Step 4. Open the numeric keypad
You will need to enter a code on the keypad to open the Services menu. Once you open it, enter the following code: *# 197328640#
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Step 5. Select [1] UMTS
After entering the code, the phone will automatically open the ServiceMode menu. In this menu you will have to choose [1] UMTS. Press the menu item on your screen to select it. If you choose the wrong option, press the Menu button on your phone and choose Back.
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Step 6. Open the Debug menu
In the UMTS menu, select [1] DEBUG SCREEN.
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Step 7. In the Debug menu, select [8] PHONE CONTROL
This will open an additional menu that allows you to change your device's settings.
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Step 8. Select [6] NETWORK LOCK
This controls the SIM unlock feature.
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Step 9. Select [3] Lost SHA256 Off
After choosing this item, wait about 30 seconds.
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Step 10. Press the Menu button and select Back
You will return to the NETWORK LOCK menu.
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Step 11. Choose [4] NW Lock NV Data INITIALLIZ
Wait about a minute after selecting this option.
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Step 12. Reboot your device
You will not receive any confirmation that the transaction was successful. If your phone connects to the new SIM network, it means the process worked.
Advice
- Before buying an unlock code, make sure your phone is locked. In most cases, if you find that your phone was unlocked after purchasing the code, you will not get a refund.
- Make sure you buy the unlock code from a reputable company. It may happen that some may sell you a counterfeit one.