Unlocking an O2 phone to use a different SIM card.

[Anonymous]

hi   im abit confused about what to to and could do with some help. (i tried asking before but have had to set up an account to post so i dont know if it worked so sorry if this is a repeat..) 

my sister has given me her old samsung galaxy s3 as she has upgraded her contract phone (a couple times since using this one) i use a Tesco pay as you go sim and have just swapped my number over to a micro sim so it fits. but my problem is that the phone still says no sim card even when its in there. i assume this is because its locked to O2. Can i unlock the phone if its not recognising a sim or do i have to get an O2 sim to be able unlock it.. and if i use someone elses will it effect thier phone/contract? 

it might jus be me not understanding things but hope you can help or just explain it abit for me thanks

[MI5 · Accepted solution]

A tesco sim will work in an O2 locked phone so the sim is either faulty or has been inserted into the wrong slot (both sim and sd slot are side by side on S3).

[Anonymous]

ok thanks  

im more confused now not sure what to do. at least dont have to worry about trying to get it unlocked.

i checked and the sim works in my old phone but when in the samung still says no sim inserted. its in the correct slot and clicked down but just doesnt seem to acknowledge it 😞

[MI5]

Maybe sim reader is faulty in the phone?

[Anonymous]

if its is whats wrong.. any ideas how to fix it/ anything i can do? 

[MI5]

They are about £10-£15 to buy and easy to replace, if it is the sim reader, but it might be a good idea to try your local phone repair shop or market stall to get it checked properly.

[Anonymous]

ok thakyou for helping

ill try go to shop and see what they can do 

[MI5]

Let us know how it goes