What To Do: If You Want To SIM Unlock A HTC One M8

Last updated: July 1, 2020.

The HTC One M8

The HTC One M8 is a great device that is available through several carriers all around the world.  If your particular device is carrier branded, to Sprint, T-Mobile, AT & T, Verizon, for example, and you want to have your device SIM-unlocked, we have a few methods for you.


Method 1: Request Your Carrier For Unlock Code To SIM Unlock HTC One M8

This is the easiest and simplest method of the three methods in this guide.  You can do this is you’ve complied with your carrier’s requirements and you’ve been under contract for around 18-24 months.  Just request an unlock code by contacting your carrier helpline or their service center. Here’s the  the whole procedure.

  1. Find out your phone’s IMEI code.  To do so, open dialpad / phone on your device and type “*#6#”. You should see your IMEI code now.  Write it down.
  2. Call your service provider or a nearby service center. Request a SIM unlock code for your device.
  3. You will be asked for your IMEI number. When you’ve given it, your going to need to wait 1 – 3 working days but they will then send you your unlock code via e-mail.
  4. Insert your SIM card into your unlocked HTC One M8.
  5. Restart your device.

Method 2: Changing Super CID To SIM Unlock HTC One M8

If you are an Android power user and have gained S-Off on your HTC One M8, you can use this method. CID determines your phone region of your phone and changing your CID code will prompt your device to unlock carrier restrictions changing the region status of your device. Change CID by following the steps listed  below.

  1. If you haven’t already gained S-Off, do so.
  2. Now you need to change your device’s Super CID to “11111111″”.
  3. Insert your SIM card into your unlocked HTC One M8.
  4. Restart your device.

Method 3: Universal SIM Unlock Using SIEEMPI To SIM Unlock HTC One M8

This method is recommended only if you don’t feel like tweaking the device’s CID or if the first method failed.  The reason we’re leery of this method is because we’re not entirely sure how SIEEMPI works and there are some concerns regarding user privacy as you will need to trust SIEEMPI with both your email and your phone’s IMEI number. While we haven’t heard any complains or issues from people who have used SIEEMPI, we still recommend users only use this method as a last resort.

  1. If you haven’t already gained S-Off, do so.
  2. Head to SIEEMPI page.  You will be asked to fill out a form with your email, mailing address and the IMEI code of your device.
  3. When you’ve filled out the form, a config file will be emailed to you.
  4. Download  config file and copy it to your device’s SDcard.
  5. Boot device into the bootloader by first turning it off  completely then turning it back on by pressing and holding volume down and power key together.
  6. In bootloader mode, highlight “SIMLock” by using the volume up and down keys to navigate and pressing the power key to select it.
  7. Config file will be executed.
  8. Follow the on-screen instructions.
  9. Insert SIM and reboot device.

Have you unlocked your HTC One M8?

Share your experience in the comments box below.


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