Upgrading to 4.2.1 without losing app data?
I've had some problems upgrading my 3GS (new bootrom) from 4.0.1 to 4.2.1.
First I got error 3194 and then I solved that by starting TSS server in TinyUmbrella (I have pretty much all SHSHs saved since 3.1.2).
But after that I ran into a error 21 code and I had to create a new user account on my pc (yes it's a Windows PC btw) in order to get past this.
What I'm doing is that I'm shift+clicking on "Upgrade" and I choose my 4.2.1 IPSW, it verifies and then "iTunes it preparing your device for upgrade" appears. But now it stalls and error 1604 cancels the process. The phone gets stuck in recovery and I have to kick it out with TinyUmbrella.
Now, I know I'm pressing shift+Upgrade and not shift+Restore because I have so much application data that I don't want to lose and I imagine that will happen if I choose shift+Restore. Am I right with this thought or will it not delete all my apps and data even if I try shift+Restore?