error message

[kate2476]

I have downloaded the file iphone1,1_1.1.1_3A109a_restore.ipsw
every time I try to downgrade, I do get the error 1015, but my phone shows the new Itunes screen with the plug and iTunes disc. I am using Itunes 7.5 I would appreciate any help.

 

[abijnk]

As per most of the guides out there, use itunes 7.4.2