Network Unlock or IMEI Issues
Seeing “SIM network unlock PIN,” “device not recognized,” or IMEI errors on Android or iPhone? This troubleshooting guide covers the most common unlock and IMEI problems—including locked devices, blacklisted IMEIs, and unlock code errors—and provides step-by-step solutions for both platforms. Restore network access and resolve device restrictions quickly.
Common Symptoms
“SIM network unlock PIN” or “Network locked” error
Device says “Invalid SIM” or “Not recognized”
IMEI blocked, blacklisted, or not found
Unable to use device on other carriers
Step by Step Troubleshooting
Android
Check Network Lock Status
Settings > About Phone > Status > Network. See if device is locked.Insert SIM from Another Carrier
If prompted for unlock code, device is locked.Request Unlock from Carrier
Contact carrier for unlock eligibility and process.Enter Correct Unlock Code
Use code provided by carrier. Retry only as instructed.Check IMEI Status
Dial *#06# for IMEI. Check at carrier or online blacklist checker.Resolve Blacklisted IMEI
Contact original carrier if IMEI is blocked or reported lost/stolen.Restart Device
Contact Carrier or Dealer if unresolved.
iPhone
Check Network Lock Status
Settings > General > About > Carrier Lock.Insert SIM from Another Carrier
If “SIM Not Supported” appears, device is locked.Request Unlock from Carrier
Contact carrier for unlock eligibility and process.Check IMEI Status
Settings > General > About > IMEI. Check at carrier or online blacklist checker.Resolve Blacklisted IMEI
Contact original carrier if IMEI is blocked or reported lost/stolen.Restart iPhone
Contact Carrier or Dealer if unresolved.
Troubleshooting Flowchart (Text Outline)
Device network locked?
Yes → Request unlock from carrier
No ↓IMEI valid and not blacklisted?
No → Contact carrier to resolve
Yes ↓Correct unlock code entered?
No → Enter correct code
Yes ↓Restart device
Still not working?
Yes → Contact carrier or dealer
Pro Tips / Dealer Notes
Too many incorrect unlock attempts may permanently lock the device—always verify code first.
Blacklisted IMEIs cannot be used on most networks—only the original carrier can remove a blacklist.
Some prepaid or subsidized phones require account in good standing before unlock.
FAQs
Q: Why is my phone asking for a network unlock code?
A: The device is locked to its original carrier—contact them for an unlock code or eligibility.
Q: What does it mean if my IMEI is blacklisted?
A: The device is reported lost, stolen, or unpaid; only the original carrier can remove it from the blacklist.
