how to alter itunes

[n0n_0perational]

sorry if this has been said but im new to the mac filesystems and dont know where everything is at,

this is the step im trying to do as im stuck with my phone at 3.1, its jailbroken via 3.1.3 but i get no service


From Saurik's Blog

All we need, then, is to make iTunes use it. Luckily, most operating systems also have the ability to locally define bypasses on specific hostnames through a file called hosts. Using this, we can redirect requests to Apple's signature server to Cydia.
So, open the file C:WindowsSystem32driversetchosts (Windows) or /etc/hosts (Mac OS X) and add the following entry to the bottom of the file.

74.208.105.171 gs.apple.com

Now, when iTunes thinks it is talking to Apple, it is talking to Cydia instead. Doing this will allow iTunes to access signatures already stored by Cydia's "on file" feature.

cydia showed a ID on file also if that helps with my problem?/

[BlackWolf]

the file is exactly where he described: /etc . only problem is that that folder isn't always visible. You can use the "go to adress" feature to get there ... press
cmd+shift+G in finder to open it, then you type in /etc and go there :-)

oh and btw: that file can't be written to normally. best course of action is, copy it to your desktop, edit it there, then copy it back :-)

[confucious]

Why do you want to downgrade?
If you have no service you have either selected activate in pwnage when you are on an official carrier or not installed UltraSn0w if you're not. Either way, no need to downgrade.