no service

I have iphone 3gs with 6.15.00 baseband with ios 4.33 and I deside to upgrade it to 5.0.1 after successful upgrade on my other iphone 4. After the procedure with iTunes the iphone 3gs has successful upgrade and I go to configure It. After all operation I saw that there is no signal and it says “No service” after Searching… I insert another sim but no luck.. Wrote in the net that other people has the same problem like mine but nobody can’t answer it. I downgrade to 4.3.3 but no luck again.. the same No service .. Now I was sure that there is not the problem in the ios , may be in the baseband ? The sim card worked in other phone with no problem. Any way, I’ve got it.. here is how:

I upgrade again in ios 5.0.1.

Jailbreak with Redsn0w 0.9.9b9d but first i click on Extras , select the ios 5.0.1 ipsw , than go Jailbreak and click Install Cydia, Install iPad baseband, Deactivate – this one I think is very important because i use this method before without click in deactivate and No service.. 🙂 Than go jailbreak – drink cup a coffee or etc ;]

Final step is to configure the telephone again , the no service message is still there but after I put location Services – No and voala! My carrier came back and everything is back to normal. My phone is unlocked and there is now need to install ultrasn0w. That’s it.