Before attempting any IMEI change, diagnose your current module. You might find the problem is not IMEI-related.
Step 1: Read current IMEI Open Windows Command Prompt as Admin:
netsh mbn show readyinfo interface=0
Or use Linux:
mmcli -L
mmcli -m 0 --3gpp-get-imei
Step 2: Check blacklist status
Enter the IMEI at swappa.com/esn or imei.info. If reported lost/stolen, no amount of hacking will make it work long-term. fibocom l850-gl change imei
Step 3: Update firmware
Lenovo/Dell issue critical firmware updates via Windows Update (for their branded modules). Install Fibocom L850-GL Firmware Update from Lenovo Vantage or Dell Command Update. Newer firmwares do not change IMEI but improve carrier compatibility.
Step 4: Manual carrier whitelist request Call your carrier’s technical support. Say: “I have a laptop with built-in cellular. My IMEI is XXXX. Please add it to the allowed device database.” Some carriers (e.g., AT&T) have a web form for this.
The Fibocom L850-GL is an LTE Cat 9 M.2 module commonly found in: Before attempting any IMEI change, diagnose your current
It uses Intel/Altair (now Sony) chipset architecture and communicates via PCIe (USB behind the scenes). The IMEI is stored in:
Open a serial terminal (115200 baud, 8N1, no flow control).
Send AT – should return OK.
Requirements:
Steps (high-level):
Success Rate: <5% on post-2019 modules. Most end with QCOM: Sahara protocol error – a brick.
AT+CGSN
Returns the current IMEI.