Hi All, I'm trying to fix my dads iPhone, not sure what happen to cause this issue. I've spent the last 2 days searching and trying to fix this. I have 3gs oldbootrom, ios 4.3.1 (currently), with baseband 6.15.00, and bootloader 06.04. I tried 4.1, 4.3, 5.0, and 5.1 but I keep getting "No service" or "no sim card". I tried custom ipsw's, tether boot still won't work. If someone could please point me in the right direction that be great.