How can i downgrade to ios4 from ios5?

Sorry,downgrading the iOS is not supported by Apple.

Do you have a reference to support your reply Ingo2711?

Why, do you doubt this? Downgrading iOS is not supported by Apple and attempting to do so is considered an unauthorized modification and will void your warranty and any right to support from Apple or on these forums.

No reference needed if you do a search on this forum you will see that once you have upgraded to a new IOS you can't downgrade.

I was hoping to find out the official blurb as I have yet to read it anywhere other than ...uh ... word of mouth.

Maybe you have it backwards. Try finding an older signed version of the iOS on the Apple website.

@marshmalllow
Copied from http://support.apple.com/kb/TS3694#error3194

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Downgrading to a previous version of iOS is not supported. If you have installed software to perform unauthorized modifications to your iOS device, that software may have redirected connections to the update server (gs.apple.com) within the Hosts file. First you must uninstall the unauthorized modification software from the computer, then edit out the "gs.apple.com" redirect from the hosts file, and then restart the computer for the host file changes to take affect.

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