Windows 7: BSOD every 24 hours

sptd.sys        0x83e29000    0x83f22000    0x000f9000    0x4bbd3138    08/04/2010 05:28:24

Unable to load image \??\C:\Windows\gdrv.sys, Win32 error 0n2
*** ERROR: Module load completed but symbols could not be loaded for gdrv.sys
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*                        Bugcheck Analysis                                    *
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Use !analyze -v to get detailed debugging information.

BugCheck 1000008E, {c0000005, 9efb0b43, ad0bea64, 0}

*** WARNING: Unable to verify timestamp for Hookport.sys
*** ERROR: Module load completed but symbols could not be loaded for Hookport.sys
Probably caused by : gdrv.sys ( gdrv+b43 )


KERNEL_MODE_EXCEPTION_NOT_HANDLED_M (1000008e)
This is a very common bugcheck.  Usually the exception address pinpoints
the driver/function that caused the problem.  Always note this address
as well as the link date of the driver/image that contains this address.
Some common problems are exception code 0x80000003.  This means a hard
coded breakpoint or assertion was hit, but this system was booted
/NODEBUG.  This is not supposed to happen as developers should never have
hardcoded breakpoints in retail code, but ...
If this happens, make sure a debugger gets connected, and the
system is booted /DEBUG.  This will let us see why this breakpoint is
happening.
Arguments:
Arg1: c0000005, The exception code that was not handled
Arg2: 9efb0b43, The address that the exception occurred at
Arg3: ad0bea64, Trap Frame
Arg4: 00000000

Debugging Details:
------------------


EXCEPTION_CODE: (NTSTATUS) 0xc0000005 - The instruction at 0x%08lx referenced memory at 0x%08lx. The memory could not be %s.

FAULTING_IP: 
gdrv+b43
9efb0b43 f3a5            rep movs dword ptr es:[edi],dword ptr [esi]

TRAP_FRAME:  ad0bea64 -- (.trap 0xffffffffad0bea64)
ErrCode = 00000002
eax=a1aa4962 ebx=8660bec0 ecx=00003fff edx=0000ffff esi=a1aa4962 edi=00000000
eip=9efb0b43 esp=ad0bead8 ebp=ad0beae4 iopl=0         nv up ei pl nz na pe cy
cs=0008  ss=0010  ds=0023  es=0023  fs=0030  gs=0000             efl=00010207
gdrv+0xb43:
9efb0b43 f3a5            rep movs dword ptr es:[edi],dword ptr [esi]
Resetting default scope

CUSTOMER_CRASH_COUNT:  1

DEFAULT_BUCKET_ID:  VISTA_DRIVER_FAULT

BUGCHECK_STR:  0x8E

PROCESS_NAME:  GUI.exe

CURRENT_IRQL:  0

LAST_CONTROL_TRANSFER:  from 9efb0501 to 9efb0b43

STACK_TEXT:  
WARNING: Stack unwind information not available. Following frames may be wrong.
ad0beae4 9efb0501 896beb18 866710d8 00000020 gdrv+0xb43
ad0beb08 832534ac 00000000 00000020 866710d8 gdrv+0x501
ad0beb20 834553be 8645fa98 866710d8 86671148 nt!IofCallDriver+0x63
ad0beb40 834721af 896bea60 8645fa98 00000000 nt!IopSynchronousServiceTail+0x1f8
ad0bebdc 8347498a 896bea60 866710d8 00000000 nt!IopXxxControlFile+0x6aa
ad0bec10 83fb0a41 00000280 00000000 00000000 nt!NtDeviceIoControlFile+0x2a
ad0bed04 8325a43a 00000280 00000000 00000000 Hookport+0x4a41
ad0bed04 76f36344 00000280 00000000 00000000 nt!KiFastCallEntry+0x12a
03b5fe54 00000000 00000000 00000000 00000000 0x76f36344


STACK_COMMAND:  kb

FOLLOWUP_IP: 
gdrv+b43
9efb0b43 f3a5            rep movs dword ptr es:[edi],dword ptr [esi]

SYMBOL_STACK_INDEX:  0

SYMBOL_NAME:  gdrv+b43

FOLLOWUP_NAME:  MachineOwner

MODULE_NAME: gdrv

IMAGE_NAME:  gdrv.sys

DEBUG_FLR_IMAGE_TIMESTAMP:  49b9d04c

FAILURE_BUCKET_ID:  0x8E_gdrv+b43

BUCKET_ID:  0x8E_gdrv+b43

Followup: MachineOwner
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