hi
i have an iphone 3g
and i wanna restore to 4.0 and jailbreak and unlock it
but i get the 3194 error
i tried the 74.208.10.249 gs.apple.com
and that didnt work?
can anyone help me please

*BUMP*

anyone please?

Looks like apple will not allow it anymore...just restore to 3.1.3...but still can not upgrade to 4.0...started happening after 4.0.1 was released...can anybody confirm this????

yep, same thing is happening to me. I am on a 3g with 3.1.2 and i can restore to 3.1.2 but not to 4.0. Getting the 3194 error even though I thought 3g's do not need to save shsh blobs. I guess apple has found a way to block 3g's from going to firmwares back and forth now...

Try restoring to 4.0.1, then jailbreak with redsn0w and unlock with ultrasn0w..

This post by saurik explains how to downgrade...
i had the problem you had, same error, and used this method to restore to 4.0
for those too freaked out to wait... (i strongly suggest to read the full thing, it explains the why) i dont know if this will work for everyone...

Bypassing the Overlord
To this end, I have constructed a server that duplicates the functionality exposed by Apple's signature server, except using "on file" results rather than live requests.
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:\Windows\System32\drivers\etc\hosts (Windows) or /etc/hosts (Mac OS X) and add the following entry to the bottom of the file.
74.208.10.249 gs.apple.com

Caching Apple's Signature Server - Jay Freeman (saurik)

I believe that the 3G now has a soft-SHSH check for the 4.0 and 4.0.1 firmwares. This duplicates via software the hardware based SHSH check on the iPhone 3GS, 4, and iPad. There is another post in the forums discussing that if you're working with a new model phone or restoring a new firmware that the restore will fail these soft-SHSH checks if you have gs.apple.com in your hosts file and pointed at saurik's.

Try removing the line from your host file if it's there and you're not using an SHSH to restore, see what happens. I could be mixing issues as the other post involves the upgrading/downgrading of basebands, however, so this may not apply. If so, sorry about that. That said, if you do the restore and the phone kicks into recovery mode, use Firmware Umbrella to kick it out -- that should work.

There is now no way to restore error free to stock 4.0 on a 3G without cached SHSH - either use custom pwnagetool IPSW or do as n1ckn4m3 suggests with tinyumbrella. Apple no longer signs 4.0 shsh for iPhones.