iOS 4.0 Itunes says: “There is a problem with your Iphone”

Hi everyone. My case may seem a bit too long, sorry about that.

So I got this Iphone 3gs 32gb in Shanghai, China. As some of you may now, Iphones which are sold in China officially have Wifi disabled, so the grey market is full of Iphones which are taken apart, modified (Wifi added, 16gb upgraded to 32gb), jailbreaked and unlocked. That’s the kind I got. It had Cydia out-of-the-box, 3.1.3 firmware. So I used it for a while without problems, never cared to save shsh (didn’t even know about it that time), until one unhappy day I upgraded to stock 4.0.1.

Since then all I get connecting to Itunes is this message: “"There is a problem with your Iphone. We're sorry, the iphone you connected maybe be damaged and cannot be activated for service”

I tried several AT&T sim card and universal activation card (got that from dealextreme) with no result.

Custom 4.0.1 ipsw made with pwnage tool bundle didn’t work because the phone is not jailbreaked now (correct me if I’m wrong)

Here are the specs:
Model: MB715LL/A
Name: iPhone
Baseband: 05.13.04 - 6.4_M3S2
Serial: 83936….
BTW when I tried to check SN on apple website, I got this: “We're sorry, but this is a serial number for a product that has been replaced”

So the question is…any ideas to get it back to life?? If not, is there any kind of software coming which could solve the case? Like, hactivated 4.0.1 which won’t need a jailbreak or something?

you could try disabling your internet then using it with itunes,

Try to disable internet (like iRa1n) said.. Then get TinyUmbrella and try to see if you can get any of your SHSH from Cydia (since it came with cydia installed there is a chance it has backed them up)..

Tried going offline, 1600/1604 errors again. I believe there is no way to install custom firmware while on official 4.0.1 so far

You could try restoring.

Here is what ih8sn0w says on their forum:

Why Can't someone just make an app that hacktivates the iPhone 3GS/4 so I can use jailbreakme?
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In order to hacktivate, you need to patch lockdownd, it manages all of the services in the device. The only way to patch it is by replacing it with a hacktivated one. But the only way to replace it as far as I know is by having an iboot exploit to exec an unsigned ramdisk to replace it.

The only thing I could see happening is if someone caches a Phonebook SIM Activation record and uses ideviceactivate from posixninja's repo. Then uses jailbreakme, then replaces lockdownd via afc2.

I wonder if anyone's working on that...

I believe you can get around that with iRecovery.

I think iRecovery got nothing to do with those errors. iRecovery just kicks the phone out of the recovery loop. Probably what you meant is iReb, but iReb doesn't work with 3gs