I've just gotten a second hand phone from my partner. It is a Samsung Galaxy s3, which he bought from optus (my sim is vodafone). I attempted to log into my google account, but an error came up "Unfortunately Google Account Manager has stopped". I tried clearing cache as was suggested on multiple forums, but nothing work. So I tried a factory reset. However, now the error is coming up on the factory startup screen, so I cannot even set up my phone. How can I fix this?