Well,you may have an iPhone 4 locked to some network that doesn’t available in your country.And the worst case begins when you update your phone to iOS 6.0.1. Almost all the results of trying to unlock your phone may be ended up with no good news at all. Okay don’t worry if you have preserved your baseband.you are survived.This unlock is totally untethered
Check whether your  iPhone 4 have any of  baseband listed below
  1. 1.59.00
  2. 2.10.04
  3. 3.10.01
  4. 4.10.01
If you have any other baseband version the only solution you can find is IMEI unlock.
Things you need
  1. Only a Gevey Ultra sim – you can order one from ebay for 7 $
Lets Begin
Direct Download Links
If you have an iPhone 4 in an iOS version that’s lower than 6.0.1 you can still follow the steps below (all have pretty same steps)
  1. Turn off your iPhone 4
  2. eject original apple tray and take out your gevey sim with tray from pack
  3. now place a working sim card (may be one you want) on gevey sim
  4. Insert it to iPhone and turn on it
  5. Wait till phone loads and unlock it
  6. Now wait few seconds till a message comes up in black background saying “Gevey Ultra Untether”
  7. Wait about 10 seconds while checking whether phone connects to network (probably it won’t)
  8. Tap Accept and wait till your phone displays network as No service
  9. Now go to phone app and take a call to 112 (the all screen should be displayed as calling, not as Emergency call,if it dials as emergency call just repeat again from 1 st step)
  10. Hang up the call in 2-3 seconds
  11. Go to Settings App
  12. Turn on Airplane mode
  13. A pop-up will come up saying “Sim Failure”
  14. OK it and wait till your phone displays network as Invalid Sim
  15. Now wait another 5 seconds and Turn on Airplane mode again
  16. This time a pop-up will come up saying No sim card Installed
  17. Don’t Panic.Just Tap OK again and turn Airplane mode off
  18. Wait till your phone starts searching for a network
  19. In about 20 seconds you are DONE !!
Links