oops,I first thought you want to install 4.2.1
OK then,download the iOS 4.0.2 from here
http/www.redmondpie.com/download-ios-4.0.2-for-iphone-4-3gs-ipod-touch-ipad-3.2.2/
And follow the same rutine that I posted.
Just make sure you have iTunes 9.2.1 or later.
I had the same error too, and recboot did the job for me http/www.sinfuliphone.com/showthread.php?t=60144
1)Connect your iPhone
2)Shift + Restore > select 4.0.2
3)In the middle of the installation,you'll get the 3194 error
4)Open recboot > Exit recovery mode and it's done.
Unfortunately I can't upload a vid(due to extremely slow connection here);however I found few links http/www.youtube.com/watch?v=ovy0GDoWFH4
http/modmyi.com/forums/general/726374-error-3194-trying-downgrade-iphone4-4-0-2-4-0-1-a.html
http/forum.gsmhosting.com/vbb/f456/100-downgrade-4-0-2-4-0-1-error-3194-a-1096357/
Can i install ios 4.0.2 without shsh files saved? if yes, how? coz the video and links you gave said that they can work only if i had shsh files saved...
-_- You are not understanding...
How can i save shsh files now, 4.0.2 is no more on my iPhone. I accidently did reset all and it got deleted and i had never saved shsh files for that... Now is there any way to install that 4.0.2 again without shsh?
I guess I'm missing something here.
You need to install 4.0.2 without shsh files right ? If so,then I already told you how to install it(using recboot if you encountered errors),if that still doesn't work for you,then I really don't have any ideas.Best to ask in Apple forums.