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Consumer Products => Avast Free Antivirus / Premium Security (legacy Pro Antivirus, Internet Security, Premier) => Topic started by: amrc0308 on December 07, 2013, 07:47:25 AM

Title: Random BSOD apparently cause by aswSnx
Post by: amrc0308 on December 07, 2013, 07:47:25 AM
Been getting random BSOD's with Avast Svc (apparently) the cause:

Followup: MachineOwner

2: kd> !analyze -v
*                                                                             *
*                        Bugcheck Analysis                                    *
*                                                                             *

An exception happened while executing a system service routine.
Arg1: 00000000c0000005, Exception code that caused the bugcheck
Arg2: fffff80002f1841f, Address of the instruction which caused the bugcheck
Arg3: fffff88003bba140, Address of the context record for the exception that caused the bugcheck
Arg4: 0000000000000000, zero.

Debugging Details:

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

fffff800`02f1841f 0fb711          movzx   edx,word ptr [rcx]

CONTEXT:  fffff88003bba140 -- (.cxr 0xfffff88003bba140)
rax=fffff88002cedd30 rbx=000000000b4adfc0 rcx=00000000012b0000
rdx=fffff88002cedd30 rsi=0000000000000000 rdi=0000000020786e53
rip=fffff80002f1841f rsp=fffff88003bbab20 rbp=000000000000175c
 r8=0000000000000001  r9=0000000000000008 r10=0000000000000008
r11=fffff88003bbab40 r12=0000000000000000 r13=000000000b4aeba0
r14=000000000b4aec70 r15=0000000075632450
iopl=0         nv up ei ng nz na pe nc
cs=0010  ss=0018  ds=002b  es=002b  fs=0053  gs=002b             efl=00010282
fffff800`02f1841f 0fb711          movzx   edx,word ptr [rcx] ds:002b:00000000`012b0000=????
Resetting default scope



PROCESS_NAME:  AvastSvc.exe


LAST_CONTROL_TRANSFER:  from fffff88002c3cb3a to fffff80002f1841f

fffff880`03bbab20 fffff880`02c3cb3a : 00000000`0b4adfc0 00000000`00000000 00000000`20786e53 00000000`00000000 : nt!RtlCompareUnicodeString+0xb
fffff880`03bbab60 fffff800`02c7ae53 : fffffa80`076e6b50 fffff880`03bbaca0 00000000`0b4adfa8 00000980`00000000 : aswSnx+0x2cb3a
fffff880`03bbabb0 00000000`77b513ba : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : nt!KiSystemServiceCopyEnd+0x13
00000000`0b4adf88 00000000`00000000 : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : 0x77b513ba

fffff880`02c3cb3a 85c0            test    eax,eax


SYMBOL_NAME:  aswSnx+2cb3a

FOLLOWUP_NAME:  MachineOwner


IMAGE_NAME:  aswSnx.sys


STACK_COMMAND:  .cxr 0xfffff88003bba140 ; kb

FAILURE_BUCKET_ID:  X64_0x3B_aswSnx+2cb3a

BUCKET_ID:  X64_0x3B_aswSnx+2cb3a

Followup: MachineOwner
Title: Re: Random BSOD apparently cause by aswSnx
Post by: fiesata on December 07, 2013, 01:34:36 PM
I have been using avast for years without a problem until recently - my Windows 7 machine has been crashing most days

To cut a long story short I narrowed the problem down to Avast

I used verifier.exe to stress the drivers for Avast only and PC crashed every time

I used safe mode to turn off verifier.exe and rebooted no crash - uninstalled Avast and no problems since

I like Avast but think there is definitely a problem with latest version

Try using verifier.exe (assuming a windows machine) check only avast


type verifier into search
open program
select > create custom settings (for code developers)
next > standard settings
next > select driver names from a list
when loaded check Avast drivers only - reboot machine
let it run
If it crashes go into safe mode turn off verifier (turn off existing settings), reboot, uninstall Avast- see if that solves the problem- come back to me if you  need any more help
I have installed AVG as a temp solution
Title: Re: Random BSOD apparently cause by aswSnx
Post by: lusi83 on December 15, 2013, 10:25:14 AM
Hi I've got this too...
4  BSODs from 2/11 to yesterday :(, first BSODs in 3 years of having this machine! decided it wasn't random
Just learned how to use microsoft debugger and discovered all  minidumps say problem probably caused by aswSnx.sys
Similar report to Amcr -could cut & past my debugger report if nec too ...
Running Windows 7 home premium SP1
(but use Access 2002 - which confuses MS updates -thinks its an XP machine sometimes  ;))

Any advice - or a fix ?
Title: Re: Random BSOD apparently cause by aswSnx
Post by: fiesata on December 15, 2013, 10:33:59 PM
Hi Lusi

Have a look at my reply above

There appears to be no fix at present that I know of other than to uninstall Avast until the problem is solved

Unless anyone can tell me differently

What brand is your machine e.g Acer Asus HP etc just wondered if there could be a conflict amongst certain machines
Title: Re: Random BSOD apparently cause by aswSnx
Post by: lusi83 on December 16, 2013, 10:57:08 AM
Sorry just seen your reply ...
Mines a Samsung NP300 (series 3 -the cheapest!), Intel core i5 (dual) processor (I think sandy bridge) , 4GB ram  - bought mar/feb 11 
Looking at my BCCode (3b) - usual causes were graphic drivers, antivirus or memory mapping.
Windows debugger says it is the aswSnx.sys causing the problem -
but before I wondered (cos I don't really understand!) if it was something to do with the dual core ...
Mine had BSOD on the 2, 9, 20 of Nov and 9 and 14 of Dec. (wondering if that was connected to updates?)
I work from home and it is my personal computer - I use it every day for hours...I'm very bad at not shutting down just sleep or hibernate.
Twice I know it was just after waking it up, then once using thunderbird (don't use very often use to archive web based email) but the last time it was while browsing the web... 
Assuming Avast know it is a bug? I'm not overly worried - I was worried it was a sign the HD was about to fail...

(Actually I'm happy I now know how to use the debugger - long story but I have an ancient Dell was going to give my daughter - it keeps blue screening, I know it is a driver problem but can't remember which one -had the same problem after a clean install in the past ...when I get a minute I'll on it on the debugger and make a 6 yo happy!!) 
Title: Re: Random BSOD apparently cause by aswSnx
Post by: fiesata on December 16, 2013, 10:36:34 PM
Blue screen view (download for free) will also isolate the problem

When PC's first came out graphics cards were often failing but these days they hardly ever fail you could check you have the latest graphics driver, you could also test your RAM - mem test is good but it takes (what seems like) forever - several hours for a full test  a quick check can be made using the inbuilt Windows Memory diagnostic (just type it into search) but it appears  like it could be avast - I just wish there was a solution
Title: Re: Random BSOD apparently cause by aswSnx
Post by: amrc0308 on January 02, 2014, 04:36:37 PM
Can report I updated to the latest version (2014.9.0.2011) and it is continuing, but now with greater frequency.   Not going to uninstall, I paid for the program.  Would be nice to have it not crash though.
Title: Re: Random BSOD apparently cause by aswSnx
Post by: jwoods301 on January 02, 2014, 07:35:06 PM
If you are not using the Avast Sandbox feature (my firewall handles those duties), download Autoruns from Sysinternals.com and run the program.

http://technet.microsoft.com/en-us/sysinternals/bb963902 (http://technet.microsoft.com/en-us/sysinternals/bb963902)

When it completes its scan, click on the Drivers tab, locate aswSnx, and uncheck it.

I have been running without it loading and eveything else works fine.
Title: Re: Random BSOD apparently cause by aswSnx
Post by: lusi83 on January 07, 2014, 09:52:50 PM
Just tried autoruns - and it won't let me uncheck aswSnx - comes up with access denied - even though I'm running it as the administrator ...
Just had another BSOD (after the update) - again windows debugger is saying caused by AswSnx - really getting to the point of serious thinking of getting rid of Avast ...as a long term user who can't recommend it enough feeling a bit sad and frustrated...
And a quick search shows I'm not the only person with this problem...
Title: Re: Random BSOD apparently cause by aswSnx
Post by: fed555 on January 07, 2014, 10:10:03 PM
Hi lusi, if you don't have do this yet ulpload the dump of yours BSOD that shuld be in C:\Windows\Minidump to ftp://ftp.avast.com/incoming!  Place them in an archive with your username and than post here the name of the archive! This is very useful for developer to identify and solve bug!
Title: Re: Random BSOD apparently cause by aswSnx
Post by: lusi83 on January 08, 2014, 02:08:57 PM
Can't get it to upload to that ftp - using firefox with firefoxftp add on - it says failed to upload...
Have pasted the debug file into notepad and attached it here - don't know if that is any help or if you can help with the ftp - or if there is another way of getting the file to you
Starting to feel out of my depth now - thanks!

Title: Re: Random BSOD apparently cause by aswSnx
Post by: fed555 on January 08, 2014, 02:33:14 PM
Hi, i'm a semple user of avast as you! If you have internet explorer and copy and paste the adderss of avast ftp server you see the istructions to open it (alt - displays - open ftp in windows explorer) than you can copy and paste the archive! if you cant't do tha sand it via mail to
Code: [Select]
kominek@avast(dot)com with the link of this post