- 1). Find out your phone's IMEI (International Mobile Equipment Identification) number. This number is an ID specific to each handset. In order to find this number, type in *#06# on the phone. Note down the 15-digit number that appears on the screen.
- 2). Go to a website that provides lock codes for Nokia N81. You can find links to some websites in "Resources" below.
- 3). Provide the website with your cell phone's IMEI number, current network provider, manufacturer and cell phone model number (N81 in this case). It may take 5 to 10 days for the code to reach you by email.
- 4). Switch off the phone and take out the SIM card.
- 5). Turn on your phone once again and enter the lock code that you obtained from the website. Your phone screen will show the message "SIM restriction off." Your phone is now ready for use with other network service providers.
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