Windows 7 - BSOD windows 7 x64; 3x this week; help with analysis

Microsoft (R) Windows Debugger Version 6.11.0001.404 X86
Copyright (c) Microsoft Corporation. All rights reserved.


Loading Dump File [C:\Users\K\Desktop\041510-16504-01.dmp]
Mini Kernel Dump File: Only registers and stack trace are available

Symbol search path is: SRV*F:\symbols*http://msdl.microsoft.com/download/symbols
Executable search path is: 
Windows 7 Kernel Version 7600 MP (8 procs) Free x64
Product: WinNt, suite: TerminalServer SingleUserTS
Built by: 7600.16539.amd64fre.win7_gdr.100226-1909
Machine Name:
Kernel base = 0xfffff800`02a55000 PsLoadedModuleList = 0xfffff800`02c92e50
Debug session time: Thu Apr 15 11:34:31.167 2010 (GMT-4)
System Uptime: 0 days 0:29:52.197
Loading Kernel Symbols
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Loading User Symbols
Loading unloaded module list
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*                        Bugcheck Analysis                                    *
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Use !analyze -v to get detailed debugging information.

BugCheck A, {0, 2, 0, fffff80002ac97b6}

Unable to load image \SystemRoot\system32\DRIVERS\vfilter.sys, Win32 error 0n2
*** WARNING: Unable to verify timestamp for vfilter.sys
*** ERROR: Module load completed but symbols could not be loaded for vfilter.sys
Probably caused by : vfilter.sys ( vfilter+29a6 )

Followup: MachineOwner
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4: kd> !analyze -v
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*                        Bugcheck Analysis                                    *
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IRQL_NOT_LESS_OR_EQUAL (a)
An attempt was made to access a pageable (or completely invalid) address at an
interrupt request level (IRQL) that is too high.  This is usually
caused by drivers using improper addresses.
If a kernel debugger is available get the stack backtrace.
Arguments:
Arg1: 0000000000000000, memory referenced
Arg2: 0000000000000002, IRQL
Arg3: 0000000000000000, bitfield :
    bit 0 : value 0 = read operation, 1 = write operation
    bit 3 : value 0 = not an execute operation, 1 = execute operation (only on chips which support this level of status)
Arg4: fffff80002ac97b6, address which referenced memory

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


READ_ADDRESS: GetPointerFromAddress: unable to read from fffff80002cfd0e0
 0000000000000000 

CURRENT_IRQL:  2

FAULTING_IP: 
nt!KeSetEvent+226
fffff800`02ac97b6 488b09          mov     rcx,qword ptr [rcx]

CUSTOMER_CRASH_COUNT:  1

DEFAULT_BUCKET_ID:  VISTA_DRIVER_FAULT

BUGCHECK_STR:  0xA

PROCESS_NAME:  svchost.exe

TRAP_FRAME:  fffff880096bac70 -- (.trap 0xfffff880096bac70)
NOTE: The trap frame does not contain all registers.
Some register values may be zeroed or incorrect.
rax=fffffa800a912578 rbx=0000000000000000 rcx=0000000000000000
rdx=0000000000000001 rsi=0000000000000000 rdi=0000000000000000
rip=fffff80002ac97b6 rsp=fffff880096bae00 rbp=0000000000000002
 r8=0000000000000000  r9=0000000000000000 r10=0000000000000000
r11=0000000000000002 r12=0000000000000000 r13=0000000000000000
r14=0000000000000000 r15=0000000000000000
iopl=0         nv up ei pl nz ac po cy
nt!KeSetEvent+0x226:
fffff800`02ac97b6 488b09          mov     rcx,qword ptr [rcx] ds:0002:00000000`00000000=????????????????
Resetting default scope

LAST_CONTROL_TRANSFER:  from fffff80002ac4b69 to fffff80002ac5600

STACK_TEXT:  
fffff880`096bab28 fffff800`02ac4b69 : 00000000`0000000a 00000000`00000000 00000000`00000002 00000000`00000000 : nt!KeBugCheckEx
fffff880`096bab30 fffff800`02ac37e0 : 00000000`00000003 fffffa80`0a912570 00000000`00000003 00000000`00000000 : nt!KiBugCheckDispatch+0x69
fffff880`096bac70 fffff800`02ac97b6 : fffff880`096bae70 fffff880`03f5bb0e 00000000`00000054 fffff880`096baef0 : nt!KiPageFault+0x260
fffff880`096bae00 fffff880`03f5b9a6 : fffffa80`00000000 00000000`00000000 00000000`00000000 fffffa80`0a912560 : nt!KeSetEvent+0x226
fffff880`096bae70 fffffa80`00000000 : 00000000`00000000 00000000`00000000 fffffa80`0a912560 00000000`00000000 : vfilter+0x29a6
fffff880`096bae78 00000000`00000000 : 00000000`00000000 fffffa80`0a912560 00000000`00000000 fffff880`03f5b42b : 0xfffffa80`00000000


STACK_COMMAND:  kb

FOLLOWUP_IP: 
vfilter+29a6
fffff880`03f5b9a6 ??              ???

SYMBOL_STACK_INDEX:  4

SYMBOL_NAME:  vfilter+29a6

FOLLOWUP_NAME:  MachineOwner

MODULE_NAME: vfilter

IMAGE_NAME:  vfilter.sys

DEBUG_FLR_IMAGE_TIMESTAMP:  4b048bff

FAILURE_BUCKET_ID:  X64_0xA_vfilter+29a6

BUCKET_ID:  X64_0xA_vfilter+29a6

Followup: MachineOwner
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