Downgrade from iOS 4.3.5 to 4.2.1

[john5171]

Hi,

I am trying to trade phones with my friend who has a 3g with ios 4.2.1, while I have a 3gs with 4.3.5.

I tried restoring the backups but it says that the backup from the 3gs will not install on the 3g until it is upgraded (which is not possible).

Anyone knows a way around this?

Thanks,

 

[saving107]

Their is no way around it.

You can not restore from a back-up, if the back-up is from a higher OS.

 

[mikelegacy]

Hi,

I am trying to trade phones with my friend who has a 3g with ios 4.2.1, while I have a 3gs with 4.3.5.

I tried restoring the backups but it says that the backup from the 3gs will not install on the 3g until it is upgraded (which is not possible).

Anyone knows a way around this?

Thanks,

Only way to downgrade is if you have your SHSH blobs saved from back when Apple was still signing them. Looks like you're SOL here.