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Windows 7: Frequent BSODs from ntoskrnl.exe and fltmgr.sys

10 Nov 2012   #1

Microsoft Windows 7 Home Premium 64-bit 7601 Multiprocessor Free Service Pack 1
Frequent BSODs from ntoskrnl.exe and fltmgr.sys

I'm getting frequent BSODs, and I'm unclear of the cause. They can happen when my PC is doing nothing (last one happened when I was trying to write this post!)
What I have tried:
- Run CHKDSK /F /R on all hard drives: no errors
- Run Memtest overnight: Passed all tests several times, no errors
- Norton: Run Full Scan, Power Eraser, Boot Recovery Scan: no issues
- Tested the PSU with a Power Supply Tester: All OK

BlueScreenView is telling me that the causes are:

Any suggestions on what to do next would be very gratefully received!


My System SpecsSystem Spec
10 Nov 2012   #2

Microsoft Community Contributor Award Recipient

Windows 10 Home 64Bit

Welcome to SevenForums.

Let's take a quick look at your .dmps and their usual causes first.
Usual causes:  System service, Device driver, graphics driver, ?memory
BugCheck 3B, {c000001d, fffff88007eaeba5, fffff880070f9a20, 0}
Probably caused by : SRTSP64.SYS ( SRTSP64+6aba5 )
Usual causes:  Device driver
BugCheck D1, {fffff80000e8db80, 2, 8, fffff80000e8db80}
*** WARNING: Unable to verify timestamp for npf_devolo.sys
*** ERROR: Module load completed but symbols could not be loaded for npf_devolo.sys
Probably caused by : npf_devolo.sys ( npf_devolo+338d )
Usual causes:  Defective hardware (particularly memory - but not just RAM), Faulty 
system service, Antivirus,  Device driver, NTFS corruption, BIOS
BugCheck 50, {fffff6fd500b7ed8, 0, fffff80002ed099b, 2}
Could not read faulting driver name
Probably caused by : memory_corruption ( nt!MiAgeWorkingSet+1d1 )
Usual causes:  Device driver, memory, kernel
BugCheck 1A, {41284, 5c2001, 0, fffff70001080000}
Probably caused by : ntkrnlmp.exe ( nt! ?? ::FNODOBFM::`string'+4ac3 )
Symantec Real Time Storage Protection is contributing in BSOD-s for you. Norton is often a cause of BSOD-s it self. I would suggest you to uninstall everything related to Norton and replace with Microsoft Security Essentials while troubleshooting.Recommended antivirus program for Windows 7 based on stability compared to others:-
Do not start the free trial of Malware Bytes; remember to deselect that option when prompted.

Run a full scan with both (separately) once downloaded, installed and updated.

Very old drivers of WinPcap by CACE Technologies (from year 2007) are causing BSOD-s as well. You should check for possible driver update for it. Click on the Start ► Control Panel ► Programs ► Uninstall a program ► Uninstall everything related to; WinPcap by CACE Technologies. Delete remnants of its drivers/older drivers using Driver Fusion/Sweeper REBOOT

Get the latest from > Source: Driver Reference Table
0: kd> lmvm npf_devolo
start             end                 module name
fffff880`03f72000 fffff880`03f7e000   npf_devolo T (no symbols)           
    Loaded symbol image file: npf_devolo.sys
    Image path: \SystemRoot\sysWOW64\drivers\npf_devolo.sys
    Image name: npf_devolo.sys
    Timestamp:        Fri Feb 02 15:24:05 2007 (45C30335)
    CheckSum:         00015803
    ImageSize:        0000C000
    Translations:     0000.04b0 0000.04e4 0409.04b0 0409.04e4
Your other .dmp shows lot of errors with NVIDIA.

The latest drivers for NVIDIA are a little problematic as I've heard. Click on the Start ► Control Panel ► Programs ► Uninstall a program ► Uninstall everything related to; NVIDIA Reboot the system. Now delete remnants of its drivers using Driver Fusion/Sweeper. Reboot if required

Download and install the drivers from the link of Filehippo bellow:
Run the System File Checker that scans the of all protected Windows 7 system files and replaces incorrect corrupted, changed/modified, or damaged versions with the correct versions if possible:Run Disk Check on your hard disk for file system errors and bad sectors on it:Free up the start-up, nothing except the antivirus is usually needed.
See if the system is stable after making these changes or not.

Then proceed with testing your RAM.
Take memtest. Run for 8 passes and test each stick in a know good slot for an additional 6 passes.
The goal is to test all the RAM sticks and all the motherboard slots.

Check your motherboard manual to ensure the RAM sticks are in the recommended motherboard slots. Some motherboards have very specific slots required for the number of RAM sticks installed.

If you get errors, stop the test and continue with the next step.

1. Remove all but one stick of RAM from your computer (this will be RAM stick #1), and run Memtest86 again, for 7 passes.
Be sure to note the RAM stick, use a piece of tape with a number, and note the motherboard slot.
If this stick passes the test then go to step #3.

2. If RAM stick #1 has errors, repeat the test with RAM stick #2 in the same motherboard slot.
If RAM stick #2 passes, this indicates that RAM stick #1 may be bad. If you want to be absolutely sure, re-test RAM stick #1 in another known good slot.
If RAM stick #2 has errors, this indicates another possible bad RAM stick, a possible motherboard slot failure or inadequate settings.
3. Test the next stick of RAM (stick #2) in the next motherboard slot.
If this RAM stick has errors repeat step #2 using a known good stick if possible, or another stick.
If this RAM stick has no errors and both sticks failed in slot#1, test RAM stick #1 in this slot.
4. If you find a stick that passes the test, test it in all the other motherboard slots.

If Part 2 testing shows errors, and all tests in Part 3 show errors, you will need to test the RAM sticks in another computer and/or test other RAM in your computer to identify the problem.

In this way, you can identify whether it is a bad stick of RAM, a bad motherboard, or incompatibility between the sticks.
Hope this helps for now. Let us know the results :)
My System SpecsSystem Spec
11 Nov 2012   #3

Microsoft Windows 7 Home Premium 64-bit 7601 Multiprocessor Free Service Pack 1

Thanks for the thorough response!
I've removed Norton, installed Microsoft Security Essentials and Malwarebytes and run Full Scans.
Since then I've had a BSOD, and a frozen machine.

During the reboot from the BSOD, there was a message on the screen saying "Detecting DRAM size...." and then the machine would reboot again. This happened a few times before the machine booted into Windows. Since then I've looked at the Computer Properties in Windows, Installed Memory. Sometimes it says 12 GB (8 GB usable). Sometimes it says 12 GB.
I'm currently running the MemTest scans - likely to take several days to individually do 3 sticks in 2 slots.
There appears to be an intermittent RAM problem.

Additionally, my ram is 1333MHz, but the POST and BIOS show it as 1066MHz. I'm not too fussed about the loss of speed, but would running it at 1066MHz make it *more* reliable or less?

My System SpecsSystem Spec

12 Nov 2012   #4
Microsoft MVP

Windows 7 Ultimate X64 SP1

In the Start Search type msconfig to open the System Configuration window, if UAC asks, allow it to run. Select the Boot tab and click the Advanced button. The BOOT Advanced Options window will open.
Uncheck the box for Maximum Memory if it is checked. Click OK, Apply and reboot for the change to take affect.

What is you computer make/model/self built? Using 3 RAM modules my be a problem, what are the frequency, timing, and voltage of all 3?
My System SpecsSystem Spec
13 Nov 2012   #5

Microsoft Windows 7 Home Premium 64-bit 7601 Multiprocessor Free Service Pack 1


Maximum Memory in msconfig is unchecked.

The motherboard is: Gigabyte GA-EX58-UD5 (rev. 1.0)
For 3 memory sticks, the manual says I should use DDR1, DDR3 and DDR5.

The memory is: 3 x Kingston 4GB 1333MHz DDR3 Non-ECC CL9 DIMM Memory

The Kingston website says that this memory (also available as a kit of 3 x 4GB) is compatible with my motherboard:

This is the documentation for the memory:
ValueRAM's 512M x 64-bit (4GB) DDR3-1333 CL9 SDRAM (Synchronous DRAM), 2Rx8 memory module, based on sixteen 256M x 8-bit DDR3-1333 FBGA components. The SPD is programmed to JEDEC standard latency DDR3-1333 timing of 9-9-9 at 1.5V. This 240-pin DIMM uses gold contact fingers. The electrical and mechanical specifications are as follows:

JEDEC standard 1.5V (1.425V ~1.575V) Power Supply
VDDQ = 1.5V (1.425V ~ 1.575V)
667MHz fCK for 1333Mb/sec/pin
Programmable CAS Latency: 9, 8, 7, 6
Programmable Additive Latency: 0, CL - 2, or CL - 1 clock
Programmable CAS Write Latency(CWL) = 7 (DDR3-1333)

My System SpecsSystem Spec
13 Nov 2012   #6
Microsoft MVP

Windows 7 Ultimate X64 SP1

Check in your BIOS for the proper RAM voltage and timing settings.
the latest BIOS is F13, 1/11/2012, do you have that one installed?
GIGABYTE - Motherboard - Socket 1366 - GA-EX58-UD5 (rev. 1.0)
My System SpecsSystem Spec
13 Nov 2012   #7

Microsoft Windows 7 Home Premium 64-bit 7601 Multiprocessor Free Service Pack 1

Yes, I'm on F13.
The BIOS is set to auto-detect the memory voltages and setting - I haven't tried manually overriding. The question I have: Is memory more stable if you run it slower that it states? Or no simple answer to that question?
My System SpecsSystem Spec
13 Nov 2012   #8
Microsoft MVP

Windows 7 Ultimate X64 SP1

Auto detect often sets RAM at the lowest possible frequency, not necessarily optimum though. Set the RAM to Manual and then set the timings and voltage to the RAM specs you posted.

Underclocking can make RAM more stable, but not always. It can get better performance with some fiddling with timings, that's a whole other subject though.
My System SpecsSystem Spec
13 Nov 2012   #9

Microsoft Windows 7 Home Premium 64-bit 7601 Multiprocessor Free Service Pack 1

Well I've started on the Memtests on the auto-detect setting. I may as well complete them on that setting. So far I have the following results, due to complete Saturday:
Stick Slot Start End Errors Passes
1 1 Sun PM Mon AM 0 12
2 1 Tue AM Tue PM 0 15
3 1 Wed AM Wed PM
1 3 Mon AM Mon PM 0 15
2 3 Mon PM Tue AM 0 11
3 3 Wed PM Thu AM
1 5 Fri PM Sat AM
2 5 Tue PM Wed AM
3 5 Thu AM Fri PM

(sorry about the layout - can't workout how to do a table in the reply!)
My System SpecsSystem Spec
14 Nov 2012   #10

Microsoft Community Contributor Award Recipient

Windows 10 Home 64Bit

Thanks for the update. Are you still having crashes?
My System SpecsSystem Spec

 Frequent BSODs from ntoskrnl.exe and fltmgr.sys

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