Thanks GreyWolf but GCVerify crashes.
Faulting application name: GCVerify.exe, version: 1.1.1.0, time stamp: 0x55ae44d0
Faulting module name: KERNELBASE.dll
Win 7 x64.
I attached the new syscheck after the modmii reinstallation, it seems there was something wrong about NAND access in some IOSes...