: The most "permanent" fix is to contact your carrier. Most will provide an unlock code for free if your contract is paid off or you've owned the device for a certain period. Warning on Unofficial Tools
For older devices (Samsung S8/S9/Note 8), the unlock code is not stored in plain NV memory. It is generated via an MD5 hash of the IMEI + Carrier ID. If the tool uses a wrong algorithm, it writes a corrupted code, locking the SIM permanently until re-flashed. qualcomm sim lock unlock tool fix
Ensure you have the latest Qualcomm HS-USB QDLoader 9008 drivers installed on your Windows PC. : The most "permanent" fix is to contact your carrier
| Phone Brand / Chipset | Effectiveness | Notes | |----------------------|---------------|-------| | | High (70-90%) | Many free tools work. NV edit is easy. | | SD660, SD665, SD670 | Medium (30-50%) | Some patches work; newer firmwares block diag write. | | SD845, SD855, SD865 | Low (10-20%) | Qualcomm SecureMSM / TrustZone blocks unauthorized NV writes. | | SD888 and newer | Near 0% | No public free tool works. Requires paid server (Octoplus, Chimera) with official exploit. | It is generated via an MD5 hash of the IMEI + Carrier ID
: Open the chosen unlock tool, select the specific phone model and chipset , and click the "Unlock" or "Remove SIM Lock" button.