1.) This will only work if you used the "Make My Life Easier" button within Cydia to store your ECIDs.
Mac Instructions
2.) Download BBEdit from barebones.com
3.) Once installed, open BBEdit, go to "File" then "Open Hidden." Go to Mac HD > Private > etc > hosts and open the hosts file. You will need to go to the dropdown box and select "open all types of files" to select it.
4.) Once you have the hosts file opened, go to the very bottom of the file, and paste "74.208.105.171 gs.apple.com" at the bottom. Go to file > Save.
5.) Put your phone into DFU mode. (With phone plugged in, hold home button and sleep button for ten seconds, then release the sleep button while keeping the home button pushed down, until an iTunes prompt pops up.)
6.) Option + click the Restore button, and point it to iPhone 3.0 OS, and Open. You can download the OS from here.
7.) After the restore process is finished, you can use redsnow 0.8 to jailbreak.
Windows Instructions
2.) Open Notepad with Administrative privileges (Right click on Notepad, open as administrator.
3.) Open the hosts file from C:/ > Windows > System32 > Drivers > etc.
4.) Add "74.208.105.171 gs.apple.com" to the bottom of the file, and save.
5.) Connect your phone, and put it into DFU mode (see instructions above).
6.) I believe it is shift + click to update (correct me if wrong), then point it to the 3.0 ipsw.
7.) Jailbreak with redsnow .8 (if that works on Windows...I don't have Windows, so I don't know.)
Everything should work.
Mac Instructions
2.) Download BBEdit from barebones.com
3.) Once installed, open BBEdit, go to "File" then "Open Hidden." Go to Mac HD > Private > etc > hosts and open the hosts file. You will need to go to the dropdown box and select "open all types of files" to select it.
4.) Once you have the hosts file opened, go to the very bottom of the file, and paste "74.208.105.171 gs.apple.com" at the bottom. Go to file > Save.
5.) Put your phone into DFU mode. (With phone plugged in, hold home button and sleep button for ten seconds, then release the sleep button while keeping the home button pushed down, until an iTunes prompt pops up.)
6.) Option + click the Restore button, and point it to iPhone 3.0 OS, and Open. You can download the OS from here.
7.) After the restore process is finished, you can use redsnow 0.8 to jailbreak.
Windows Instructions
2.) Open Notepad with Administrative privileges (Right click on Notepad, open as administrator.
3.) Open the hosts file from C:/ > Windows > System32 > Drivers > etc.
4.) Add "74.208.105.171 gs.apple.com" to the bottom of the file, and save.
5.) Connect your phone, and put it into DFU mode (see instructions above).
6.) I believe it is shift + click to update (correct me if wrong), then point it to the 3.0 ipsw.
7.) Jailbreak with redsnow .8 (if that works on Windows...I don't have Windows, so I don't know.)
Everything should work.