When you have seen the message (Can Not Undo Restriction) or (Not Allowed), it means one of the following: 1.) You entered 5 or more wrong codes into your phone. 2.) The phone was bought off Ebay and the seller did the same as above. 3.) You have browsed around looking at other peoples phones and assumed that the code that worked for their model, would also work on yours. All IMEI numbers are different, which means every code for different phones will be different. 4.) You kept entering the same code over and over when seeing "code error" the first time. YOU ONLY GET 5 CHANCES TO ENTER THE CORRECT CODE This also applies to 6101's and 6102's that show (phone restrictions on) 6030, 6630, 6670, 6680, 6682 & ALL N-SERIES YOU GET 3 CHANCES This means that your phone is hardlocked to the original provider and it will only work with the original provider. The only way to get the phone unlocked would be to take or send it to a professional unlocker. The hardware used to unlock the phone is called a DCT 4 clip and they usually cost in between $200.00 to $400.00 for a real one, not a fake. The unlock would only cost you about $20.00 to $30.00 for someone local (if you can find someone). I suggest calling your local privately owned electronics repair shops and ask them if they can unlock a DCT 4 type phone. If they can do this, they will know what you're talking about. If you would like to send it off to have it done ( such as http://www.iunlock.com ), it would be about $35.00 and takes about a week to get your phone back. It might take longer but you would need to ask the person that's doing it. There is no software or cable for unlocking a DCT 4 type phone (which most are). It can not be done. DCT 3 type phones can be unlocked with cable and software but the phones are rare now, and not many people have them anymore. Hopefully this explains all you need to know about how the phone was hardlocked and what you can do to get it fixed or unlocked.