This is what I did to successfully Downgrade my iPhone OS from 3.1 to 3.0.1

First off I used a laptop that was not the main PC I have been getting backups from.

You will need to install iTunes 8.2.0.23.

Make sure you have a current backup of the phone, pull off any Notes, Pictures and or other Data that could be lost.

Completely remove any version of Itunes on the Laptop and Install iTunes 8.2

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1. Connect iPhone to Laptop with iTunes 8.2
2. Hold down Shift key while pressing restore
   1. Select Firmware
   2. http://www.felixbruns.de/iPod/firmware/
3. Let it Run
   1. I got a 1015 Error at the end and the Phone is stuff in a iTunes connection mode.
4. Now Disconnect iPhone
5. Power off iPhone
6. Shutdown iTunes
7. Install iRecovery as well as move files to a easy path to get to.
8. Run the *.exe inside a command prompt and issue the following commands
   1. Launch iRecovery
      1. ./iRecovery -s
   2. Issue Commands
      1. setenv auto-boot true
      2. saveenv
      3. fsboot
   3. and Once More
      1. fsboot
9. Phone will reboot and eventually iTunes should pick it up Activate it ... and you are good to go.

I have attached all the files I used on a Windows XP PC's to pull this off.

Last but not least

1. Connect iPhone to Desktop PC (the one that has the backups)
2. Click restore from backup and pick a backup that was before you upgraded to 3.1, it should give you a nice warning if you select too new of one.
3. I then synced my Apps from the PC to iPhone and I was back to how it was running nicely with firmware 3.0.1
4. 

Attachments:

ATT_US.zip	[ ]	22 Kb
iRecoveryWin32.zip	[ ]	408 Kb