Can I Downgrade iPod touch 1G?

No Signed Firmwares Available
There are currently no signed firmwares available for iPod touch 1G.
July 14, 2008
February 22, 2008
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November 7, 2007
September 26, 2007
September 11, 2007
Can I downgrade from an iOS Beta on iPod touch 1G?
Yes. If your iPod touch 1G is running an iOS Beta, you can always restore back to the latest signed public release using Recovery Mode in Finder (Mac) or iTunes / Apple Devices (Windows).
Can I downgrade to the iOS version iPod touch 1G originally shipped with?
No. Apple permanently closes the signing window for older releases. Even though iPod touch 1G originally launched with an earlier version, Apple servers will no longer authenticate that installation.
What can I do if I cannot downgrade iPod touch 1G but experience battery or performance bugs?
You can perform a clean restore to the latest signed firmware using a computer to eliminate software glitches and corrupted cache, or await the next minor point update from Apple that includes targeted bug fixes.
Can I downgrade iPod touch 1G if the signing window has closed?
No. Apple servers reject restore verifications for unsigned builds (returning iTunes Error 3194). Unsigned firmware cannot be installed on standard Apple devices.
Will restoring or downgrading iPod touch 1G erase data?
Yes. Flashing an IPSW firmware file requires a restore that wipes on-device storage. Ensure your personal data is backed up to iCloud before proceeding.