Unable to restore in iTunes. Help??

I am trying to downgrade my pohine using iTunes. I put it in the recovery mode but the screen stays blank, but iTunes does detect the phone.

It say iphone in recovery mode. When i shift+Restore the screen turns white for a few seconds, then goes blank again.

In iTunes it goes through 1 restart stage, and starts to prepair iphone for recovery, but then fails with error 1604.

Has anyone got any ideas please?

Ive search the forum, and stickies till im blue in the face and cant seem to get anything sorted.

UPDATE!!
Afeter constant trying to downgarde in itunes, i now can not get the phone into recovery mode, and iTunes can not detect the phone. All i have is a blank screen, and can not turn the phone on.
Any advise please?

Come on guys!! Please help a man in need!!

This problem is not strange for me ,Maybe you have to,

1-Uninstall iTunes and download another version of it.(Update to iTunes 7.5 or later)
2-Restart your computer and Try a different USB port.
3-Remove extra USB devices.
4-Try restoring on a different computer.

Which firmware do you recommend i try with it?

Wich firmware are you using now?

I have just bought it, and it was on 1.1.1 but it had a repair is need no call can be make, so i attempted to restore to 1.0.2 and now its in this state.

Restore to 1.1.1 so.

Download it: http://appldnld.apple.com.edgesuite....a_Restore.ipsw


Then use the advices of abc12345 above to do your restore.

Ok. Ill give that a try, and report back. I have been trying to restore to 1.0.2 and 1.1.1 and kept getting errors (6) (9) and (1604)

Your iphone are functioning? If it so why you don't install oktoprep and do an update to 1.1.2?

I can only put it in the recovery mode 10-10 and the screen in black. ITunes detects the phone in recovery mode, so i do shift+restore to 1.1.1, but it fails with error message before completion, then goes back into blank screen recovery mode. I have tryed it with iBricker, and the screen goes green saying that i need to restore in iTunes, but it wont let me. Also i have tryed the app tabb and its only getting to stage 2 and freezing.