I'm a developer, and I have a little problem with iOS 5.1 upgrade.
So now, I want do "downgrade" iOS 5.1. I already downloaded the iOS 5 (9A334), and try to downgrade via Xcode, dragging the file to Xcode and restoring the iPad, but it's not working.
Any idea?
Downgrades are normally not supported by Apple.
You can try to put your iPhone into recovery mode to restore to the older firmware.
Here are the instructions from Apple:
http://support.apple.com/kb/HT1808
As soon as your iTunes recognizes the iPhone to be in recovery mode, hold the ALT-Key and click on the restore button. It will prompt you to select the firmware you want to restore.