To summarize:
You get a register dump here:
eax=00000000 ebx=00390320 ecx=0854ff48 edx=09e44bfc esi=00012ce1 edi=0854ff61
eip=00465c51 esp=0854ff30 ebp=00000000 iopl=0 nv up ei pl zr na po nc
cs=001b ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00010246
The eip
indicates the instruction that failed:
FAULT ->00465c51 8a441eff mov al,[esi+ebx-0x1] ds:0023:003a3000=??
The stuff at the end is the address that failed to read, which is the "usual" data segment of 23, and address 3A3000, whcih is composed of esi
and ebx
minus 1: 390320+12ce1-1. To me, that looks like an index gone bad - 3a3000 would be the first address of a new "page" in memory, so that's why it's failing at that point. 77025 bytes into an array is quite a long way, but it is of course possible that it's something else that is wrong.