iPhone 3GS not detecting my carrier after update...

[SamAzam]

I've googled extensively looking for a fix for this, I've found many problems SIMILAR to mine but none exactly the same so I'm going to give as much information as possible.

I bought an iPhone 3GS (32G) second hand from a friend. It was locked to a network which was not my own, so I took the phone to a small phone repair shop where they unlocked it for me for $50.

After this, it worked perfectly. I synced it to my own iTunes and everything was fine.

A few weeks after using it, my iTunes offered an update to iOS 4, I clicked it thinking the phone would update to the latest software, and continue to work fine.
However, when the update was complete I had this error in iTunes....

The SIM card inserted in this iPhone does not appear to be supported.
Only compatible SIM cards from a supported Carrier may be used to activate iPhone.
Please insert the SIM card that came with your iPhone or visit supported Carrier’s store
to receive a replacement SIM card.

I disconnected my iPhone and ever since then the phone will not detect my carrier. It works now like an iPod touch. It cannot make/receive calls or texts, or connect to the internet.

I have tried to restore however I get an unknown error saying the phone cannot be restored (error code 2001)

I have tried jailbreaking it, downgrading back to 3.1.3...(this didn't work due to error- "This device isn’t eligible for the requested build")
I even took it into a store of my carrier, told them of the error, and they replaced my sim saying it may fix the problem, but to no avail.

Does ANYONE know ANYTHING that can help me?
I use a macbook aluminium OS X 10.6.5

I cannot take it to an Apple store because it is second hand, and jailbroken, so I know they won't fix it.
Is it time to give up?

 

[Al3x87]

When you did the update, the unlock was lost. And 50$ for an unlock is.... to much!! You can do it at home. So, **************************.

 

[Nermal]

Do you know which network it's from? It appears that the repair shop performed an unofficial unlock, which will have been lost with the update. You should contact the network that originally sold the phone as they can probably perform an official unlock.

 

[SamAzam]

I'm with optus (in Australia) and I don't know which carrier it was originally locked to.
I managed to restore the phone, after taking the sim card out, but now it says to insert a valid SIM to activate the phone. And when I put mine in, it just goes back to the 'sim card not compatible' message in iTunes.
So I was going to unlock it again myself, but now I can't even get to the springboard to do that, I'm stuck with the picture of the USB pointing to the iTunes icon.
I think I just made my problems worse.

 

[SamAzam]

Do you think if I go buy sim cards from a few different carriers (since they're only a couple of dollars each) until I get the right one, to activate it again, that I will be able to unlock it again myself and then finally use my own original sim card with no problems once more?

 

[Nermal]

According to Apple's documents it must be locked to either Vodafone, Telstra or 3. Try those until you find which it works with. I'd suggest getting it unlocked officially once you know where it's from, so that you don't run into trouble in the future as there will likely be more updates available later.

 

[SamAzam]

Do you think it's worth trying to 'hacktivate' it before spending money on SIM cards?
If I can successfully hacktivate it, then I should be able to jailbreak then unlock it myself.

 

[Nermal]

I can't say; I've never actually owned an iPhone so my advice is limited to what I've read in the past

 

[SamAzam]

Thanks for your help

I would have saved myself a whooole heap of trouble if I had have known updating would re-lock my phone.

 

[Al3x87]

If i'm not wrong, you must activate it just once, when the contract with which was bought the phone expires.