Upgrading iphone 4 from 4.2.1 to 5.0.1

[monaal]

This sound really stupid but i tried every thing to upgrade by preserving my iphones base band .

I have a iphone 4 4.2.1
base band 03.10.01

i would like to upgrade it to 5.0.1 while preserving the baseband .

I downloaded redsn0w and created a custom firmware of 5.0.1 .
then i put my iphone in DFu mode .
then tried to restore my iphone with the custom firmware i keep getting an erro . the this firmware is not for this iphone .
cause itunes verifies the firmware with apple before installing it .
I also added the following line 74.208.10.249 gs.apple.com in the hosts file .
but still i was getting the same error.


Please help

 

[NanoNyrd]

If you do not have saved SHSH blobs for 5.0.1, then it is not possible to upgrade.

If you do have them (or Cydia has them), then you need to use redsn0w to stitch them to the IPSW file, and restore in pwned DFU mode. It is described in several other threads.