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cjcool300's profile



1 Message

Tue, Aug 25, 2015 11:09 PM

"GP103: The SIM number entered does not exist. Please check the number and enter it again."

I bought a Nokia Lumia 635 and am trying to activate it. However, on the activation screen I try to enter the SIM number and it says "GP103: The SIM number entered does not exist. Please check the number and enter it again.".


This is a brand new, unopened phone with a brand new SIM card yet I can't seem to activate it.



Community Support


15.2K Messages

6 years ago

Hi there! @cjcool300 Thanks for posting your concerns. I’m sorry to hear you are having issues with your SIM. You can get a replacement SIM free of charge from any AT&T company store.


To locate your nearest store please go to and select Store Locations & Appointments on the upper right of the site. From there you can enter your zip code and find your nearest store address, hours of operation and phone number.






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