awwwebrepie.dll crashing internet explorer

i dont use internet explorer but firefox one of my device always opens internet explorer when it starts and i normally click it close
but one of the recent updates probably installed an addon for both the brrowser
though firefox doesnt exhibit any problems internet explorer always crashes when i am clicking it close

iam pasting the windbg output below for someone who knows what to do with it

if any queries pl post back

0:008> !analyze -v
*******************************************************************************
*                                                                             *
*                        Exception Analysis                                   *
*                                                                             *
*******************************************************************************

Failed calling InternetOpenUrl, GLE=12007

FAULTING_IP: 
ntdll!RtlEnterCriticalSection+b
7c90100b 837a1400        cmp     dword ptr [edx+14h],0

EXCEPTION_RECORD:  ffffffff -- (.exr 0xffffffffffffffff)
ExceptionAddress: 7c90100b (ntdll!RtlEnterCriticalSection+0x0000000b)
   ExceptionCode: c0000005 (Access violation)
  ExceptionFlags: 00000000
NumberParameters: 2
   Parameter[0]: 00000000
   Parameter[1]: 00000034
Attempt to read from address 00000034

FAULTING_THREAD:  00000c64

PROCESS_NAME: [b] iexplore.exe[/b]

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

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

EXCEPTION_PARAMETER1:  00000000

EXCEPTION_PARAMETER2:  00000034

READ_ADDRESS:  00000034 

FOLLOWUP_IP: 
aswWebRepIE+1846f
1001846f 8b4718          mov     eax,dword ptr [edi+18h]

MOD_LIST: <ANALYSIS/>

NTGLOBALFLAG:  0

APPLICATION_VERIFIER_FLAGS:  0

BUGCHECK_STR:  APPLICATION_FAULT_NULL_CLASS_PTR_DEREFERENCE_INVALID_POINTER_READ

PRIMARY_PROBLEM_CLASS:  NULL_CLASS_PTR_DEREFERENCE

DEFAULT_BUCKET_ID:  NULL_CLASS_PTR_DEREFERENCE

LAST_CONTROL_TRANSFER:  from 1001846f to 7c90100b

STACK_TEXT:  
0161d910 1001846f 00000020 cd07e6cb 00000000 ntdll!RtlEnterCriticalSection+0xb
WARNING: Stack unwind information not available. Following frames may be wrong.
0161d9f4 1002c693 021f5b38 021fc700 cd07e51f aswWebRepIE+0x1846f
00000000 00000000 00000000 00000000 00000000 aswWebRepIE!DllUnregisterServer+0xa943


SYMBOL_STACK_INDEX:  1

SYMBOL_NAME:  aswWebRepIE+1846f

FOLLOWUP_NAME:  MachineOwner

MODULE_NAME: aswWebRepIE

DEBUG_FLR_IMAGE_TIMESTAMP:  4f56a7ca

STACK_COMMAND:  dt ntdll!LdrpLastDllInitializer BaseDllName ; dt ntdll!LdrpFailureData ; ~8s ; kb

BUCKET_ID:  APPLICATION_FAULT_NULL_CLASS_PTR_DEREFERENCE_INVALID_POINTER_READ_aswWebRepIE+1846f

IMAGE_NAME:  C:\Program Files\Alwil Software\Avast5\aswWebRepIE.dll

FAILURE_BUCKET_ID:  NULL_CLASS_PTR_DEREFERENCE_c0000005_C:_Program_Files_Alwil_Software_Avast5_aswWebRepIE.dll!Unknown

WATSON_STAGEONE_URL:  http://watson.microsoft.com/StageOne/iexplore_exe/8_0_6001_18702/49b3ad2e/ntdll_dll/5_1_2600_5755/49901d48/c0000005/0000100b.htm?Retriage=1

Followup: MachineOwner
---------

[b]0:008> lmvm aswWebRepIE[/b]

start    end        module name
10000000 100f8000   aswWebRepIE C (export symbols)       C:\Program Files\Alwil Software\Avast5\aswWebRepIE.dll
    Loaded symbol image file: C:\Program Files\Alwil Software\Avast5\aswWebRepIE.dll
    Image path: C:\Program Files\Alwil Software\Avast5\aswWebRepIE.dll
    Image name: aswWebRepIE.dll
    Timestamp:        Wed Mar 07 05:41:54 2012 (4F56A7CA)
    CheckSum:         00000000
    ImageSize:        000F8000
    File version:     7.0.1426.0
    Product version:  7.0.1426.0
    File flags:       0 (Mask 3F)
    File OS:          4 Unknown Win32
    File type:        2.0 Dll
    File date:        00000000.00000000
    Translations:     0409.04b0
    CompanyName:      AVAST Software
    ProductName:      avast! WebRep
    ProductVersion:   7.0.1426.0
    FileVersion:      7.0.1426.0
    FileDescription:  avast! WebRep Plugin
    LegalCopyright:   Copyright (c) 2012 AVAST Software

[b]0:008> ub 1001846f[/b]

aswWebRepIE+0x18455:
10018455 50              push    eax
10018456 8d4de4          lea     ecx,[ebp-1Ch]
10018459 e892410100      call    aswWebRepIE!DllUnregisterServer+0xa8a0 (1002c5f0)
1001845e 8d4720          lea     eax,[edi+20h]
10018461 c645fc07        mov     byte ptr [ebp-4],7
10018465 50              push    eax
10018466 89450c          mov     dword ptr [ebp+0Ch],eax
10018469 ff153c510710    call    dword ptr [aswWebRepIE!DllUnregisterServer+0x533ec (1007513c)]

[b]0:008> ln poi(aswWebRepIE!DllUnregisterServer+0x533ec)[/b]

(7c901000)   ntdll!RtlEnterCriticalSection   |  (7c9010e0)   ntdll!RtlLeaveCriticalSection
Exact matches:
    ntdll!RtlEnterCriticalSection = <no type information>