Sim card locked up - Cell Phones

a sim card or phone needs a puk code or is locked BECAUSE it is not active,in order to unlock a sim card,or receive a puck code,you need to either,pay the balance owed,buy a new monthly service,open a new contract with a cell service or return the sim card or cell phone to whom it belongs to,we at fixya CANNOT GIVE YOU A NUMBER TO UNLOCK YOUR SIM CARD OR PUK CODE,there is a reason why it is locked,if it was easy to get a code,then anyone could steal your phone and use it and you couldnt stop its use for at least a month.
a phone is jail broken when you alter it to work on a different cell service provider,we at fixya do not jailbreak anything,if it isn't legal,then it doesn't belong here.

Call your cellphone service provider.

phone lock

If the Nokia X6 16GB phone,displays invalid sim card message on the screen it is locked to some network.Please find out the network and country it is locked now.If it is locked to network,it will not accept other network sim card.But you saying it is accepting other networks sim card.How many network sim card have tried inserting in it?If you tried only one network sim card and it accepted that it is locked to that network.You can also try using some other network sim card.If it displays invalid sim message again.It is under network lock.To unlock it use unlock code.Visit the site Wickedunlock.com get code and unlock it easily.

If your Nokia X6 16 GB Displays invalid sim card while inserting other Network GSM sim card like MTN ?
It is locked to network.You need to specify which country and network it is locked now.I have bought an Nokia X6 16GB in INDIA but it was locked to Australia Vodafone network .I have unlocked it and now using it in USA AT&T network sim card.So you can unlock your Nokia X6 16GB from current network lock using the unlock code from the site Onlinegsmunlock.com after unlock it use with MTN network sim card or any GSM pay as you go sim card it will not display invalid sim card message.

You will most likely have to purchase a new sim card as some phones are sim card specific. Also try a jail breaking program or have it done.

It's not reading Only T-Mobile Sim card ?It's not reading other sim card also Expect Only One Sim card?
If it reads only Sim card and not reading Other Sim card like for Example T-Mobile,AT&T,Orange etc means it locked to Network ,you have to Unlock it To use any GSM Network Sim card,What is Mobile Phone Brand and Model?Find the Network ,Country it locked now? then first please You can find it locked To GSM Network or CDMA? Network CDMA Network means You cannot Unlock t to use any gsm Network Sim,Gsm Network Lock means You can Unlock it to use other Network Sim card...You can Unlock it using the Unlock code,You can get the Unlock code and instructions at here
Unlocking4u.com and Unlock it from Network Lock,then you can use with T-Mobile Network surely.

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