Urgent problem. Please help
So, I tried to root a friend's SGSII and when it boots the screen just stays there, stuck in the boot logo with the yellow triangle. I read it took some time to boot, but it has been like that too much. I dont know what to do, if I try to flash a rom with odin, it says fail and I dont know why, it never happened to me with my SGS1. I dont find any stock kernels and the stock roms download links are down. I don't want to let my friend down. Do you have any idea of what I could do?
Thanks in advance!!