Does hard reset downgrade device?

Question

I just "repaired" an iPod Touch, 4th generation (MC540BT). A friend of mine didn't use it for a year because it didn't charge. After playing with it a little; I finally managed to turn it on and it worked. She (my friend) told me that it didn't work as soon as she updated it to 6.0.1 and asked me if I can downgrade it to the previous version. I told her about hard reset but I want to know if hard reset brings it back to the iOS version that it left the factory with.

In less words: Does a hard reset downgrade device or allow me to downgrade?

Answer 1

No - If by hard reset you mean 'restoring', it will restore the device to the most recent version of iOS that is able to be installed on the device. Restoring will only let you install the last version—there's no choice.

Answer 2

If you want to downgrade your device, you have to save SHSH (see below) with third-party software like TinyUmbrella to make such restores possible.

What is SHSH?

Every time you install or upgrade your iOS, installer asks Apple if this installation is possible for this device. This answer can't be generated (Apple closed this bug). When Apple releases new iOS version for given device, answer to install outdated iOS version be always negative.