If your Nokia 1202 has a corrupted IMEI (e.g., “IMEI invalid” or “00000000000000”), the only legitimate path is to use to reflash the original backup RPL file from that specific phone — not to generate a new number.

Some people use the following code to access the service menu and potentially change the IMEI:

: *#7370# – Formats the phone's memory entirely. Check Software Version : *#0000# .

That being said, for educational purposes, here are some general steps and codes that might be used:

The following information is provided for educational and informational purposes only. Changing the IMEI of a phone is illegal in most jurisdictions (including the EU, UK, USA, and India) unless you are the manufacturer or a certified operator performing a repair on a legally owned device with a faulty IMEI. Tampering with IMEI numbers to hide a stolen phone or bypass network blocks is a criminal offense.

The process involved writing a modified “PM” (Permanent Memory) file to the phone’s EEPROM, which included a new IMEI. This and is not possible via keypad codes.

I must emphasize that modifying the IMEI code is not recommended, as it may be against the law in your country and can also lead to issues with your phone's warranty and potential security risks.

$$*#0000#$$

(like *#06# for viewing) that you can type into the keypad to permanently change the IMEI number on a Nokia 1202. Codes like *#7465625# (for network locks) or *#*#3646633#*#* (MTK engineer mode) do not work on this device.