Q: Random BSOD - Win 8.1 win32k.sys


Since today I have gotten 2 random BSOD caused by win32k.sys.

I uploaded the 2 dumps + dxdiag here

If anyone has any suggestions what is causing these BSOD please let me know. I made no big changes to the system in the past 2 days.




Both of the attached DMP files are of the SYSTEM_SERVICE_EXCEPTION (3b) bug check.

This indicates that an exception happened while executing a routine that transitions from non-privileged code to privileged code.

This error has been linked to excessive paged pool usage and may occur due to user-mode graphics drivers crossing over and passing bad data to the kernel code.

BugCheck 3B, {c0000005, fffff960000c3632, ffffd00023e2ced0, 0}

0: kd> ln fffff960000c3632
(fffff960`000c35d0)   win32k!HANDLELOCK::vLockHandle+0x67   |  (fffff960`000cd7a0)   win32k!HANDLELOCK::vUnlock

^^ The exception occurred in win32k!HANDLELOCK::vLockHandle.


1. Uninstall both ASRock V Drive + Ram Disk ASAP.

2. Remove and replace avast! with Windows 8's built-in Windows Defender for temporary troubleshooting purposes as it's likely causing conflicts:

avast! removal -

Windows Defender (how to turn on after removal) -

3. In your loaded drivers list, dtsoftbus01.sys is listed which is the Daemon Tools driver. Daemon Tools is a very popular cause of BSOD's in 7/8 based systems. Please uninstall Daemon Tools. Alternative imaging programs are: MagicISO, Power ISO, etc.

4. Uninstall cFosSpeed - The Internet Accelerator ASAP, I see it cause BSOD's all the time.

5. Ensure you have the latest video card drivers. If you are already on the latest video card drivers, uninstall and install a version or a few versions behind the latest to ensure it's not a latest driver only issue. If you have already experimented with the latest video card driver and many previous versions, please give the beta driver for your card a try.



Debugger/Reverse Engineer.

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Views: 806 Last updated: February 21, 2018 Applies to: