Apple update iPhone 3GS v3.0 to iOs4.0

[jan777]

Device: Iphone 3gS
Firmware: 3.0
Jailbreak tool if used: I dont know, jailbreaked by a "friend" ("friend" is now gone.)
AppSync installed: YES
Unlock tool if used: Yes, unlocked by same "friend" so it can be used in the Philippines, but now, I'm back at Canada, it is back on its original carrier.
Computer OS: Windows XP


What your problem is:
So, I want to update to v4.0 or v4.1 (or whichever you guys recommend). Mainly becuase I cant use Installous and some apps dont work.
Can anyone give me a step by step instructions on how to do this?
Also, i would like to keep my personal data (photos mainly and some apps that were actually paid for.)
Please help me, THANKS!
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I already had this posted on another forum, but I want a second opinion.
A guy there said that i should back up in itunes, update to 4.1 in itunes, then use limerain to jailbreak.

 

[iFish]

First back it up using iTunes

Well...So. First I want you up update to stock iOS 4.1 (via iTunes)

Then, Use greenpois0n to jailbreak.

Now you should have an app called "Loader" Use that to install Cydia

Then do the same thing you did to get installous last time, You just add it to cydia's sources, And install Appsync for OS 4.1 and install installous!

Presto, you're finished!

 

[Joktan]

And about the baseband unlock,if you are on atnt then you don't need to worry about that.

 

[iFish]

I am pretty sure he's in Canada. So, AT&T does not exist.

And if he wants to preserve his baseband (which he didn't mention)

He would need to use PwnageTool