SIM Not Valid


New Member
Sep 13, 2015
Hey what's going on guys - new here and just wanted to ask a quick question.

I recently purchased an iPhone 5 running IOS 6 off a private seller and I can't seem to get past the initial setup screen. He didn't mention what carrier the phone is locked to so I attempted a few different SIM cards, both received full service after inserting but would not let me move forward 'SIM Not Valid - The SIM card that you currently have installed in this iPhone is from a carrier that is not supported under the activation policy that is currently assigned by the activation server'.

Unsure whether the phone is blocked or whether i've missed out the right SIM card that actually works as I have only tried two (Three & Giffgaff). Any help would be much appreciated, thanks!