Topic: 1000001: Using the System File Checker @ AskWoody

1000001: Using the System File Checker

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- - February 2, 2017 at 5:48 am #83021
    
    woody
    Manager
    
    AKB1000001: Using the System File Checker
    
    By @NoelCarboni
    
    Published 2 Feb 2017 rev 1.0
    
    Microsoft provides a self healing feature for Windows called Windows File Protection. It’s been around for a while, actually. Windows File Protection helps keep Windows sane by watching for un-sanctioned changes to system files. A particular program called the System File Checker (SFC) is provided as part of Windows File Protection:
    
    https://blogs.technet.microsoft.com/askcore/2007/12/18/using-system-file-checker-sfc-to-fix-issues/
    
    The short story is that you want to get a little geeky you can use SFC to see if your Windows installation is healthy. It’s quite easy – just start an elevated CMD window and run this command:
    
    SFC /VERIFYONLY
    
    Go ahead and try it. It’ll run for a few minutes – or maybe even a few tens of minutes – and it will thoroughly check all your Windows system files.
    
    Note that just checking your system’s health shouldn’t harm anything. It’s only checking, not changing things. You might even get a warm and fuzzy feeling when SFC says all’s well!
    
    But the all important question is: What do you do if SFC reports an error?
    
    SFC can be asked to try to repair basic problems it finds with the Windows system files using your local servicing database (hey, some of the data in all those gigabytes of Windows installation can actually be useful). Specifically If the above SFC /VERIFY command says there are errors, you can try a next step: Run SFC again but this time with a different switch, where you ask it to actually fix any errors it finds.
    
    Note that if you have been hacking Windows system files yourself, you might have caused the errors yourself and an SFC repair will likely undo those hacks. I personally recommend never doing hacks that change system files and break Windows File Protection. It’s quite possible to run a customized and tuned up Windows 8 system that still passes SFC checks – I do!
    
    This command asks SFC to repair any problems it finds:
    
    SFC /SCANNOW
    
    It might tell you that it found and repaired the errors. If so, that’s great and here comes that warm and fuzzy feeling. You’re all done!
    
    But – unfortunately – there are some errors this command can’t fix. Like any files, the servicing database itself in Windows can become corrupted, making an SFC repair impossible. It can and does happen.
    
    If SFC /SCANNOW informs you that it could not repair errors, you can dig through the file C:\Windows\Logs\CBS\CBS.log to find out why. It’s cryptic and voluminous, but a search for the string “cannot repair” often turns up the key clues. Pay attention to the dates and times as data from multiple runs accumulates in that log file, but persistence pays.
    
    Last month I observed that an uncorrectable error was introduced on my Windows 8.1 system after I installed the December set of “Group A” (everything cumulative) updates:
    
    Specifically, SFC reported (via CBS.log) that the file Sound Recorder.lnk was corrupted and that the corruption couldn’t be repaired because the “source file in the store was also corrupted”.
    
    Fortunately, with Windows 8 and newer there’s a way to escalate the automatic repair process to yet another level – and it really works – using a DISM command. DISM is the Deployment Imaging and Servicing Management tool provided with Windows. Yep, now we’re gettin’ seriously geeky. Just like a crack IT professional.
    
    Specifically, if you find yourself with errors that SFC just can’t repair, clear your schedule for 10 minutes or so and try this command:
    
    DISM /Online /Cleanup-Image /RestoreHealth
    
    It actually goes online to the Windows Update site and does what it can to repair the local servicing database on your running system! After running it, SFC /SCANNOW might actually be able to repair those errors it couldn’t repair before!
    
    You can find more information on Microsoft’s site about DISM:
    
    https://technet.microsoft.com/en-us/library/hh824869.aspx
    
    Once the DISM command is done – which may take quite a while so be patient – go back and try the SFC /SCANNOW command again. There’s a good chance it will now succeed and you might actually get back to that warm feeling that Windows is healthy.
    
    It worked for me.
    
    10 users thanked author for this post.
    
    2Mike, cmptrgy, Microfix, SueW, Elly, WildBill, Steve S., dononline, ch100
    
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  - February 2, 2017 at 7:49 am #83189
    
    anonymous
    Guest
    
    Quoted from
    http://www.howtogeek.com/222532/how-to-repair-corrupted-windows-system-files-with-the-sfc-and-dism-commands/
    
    “On Windows 7 and earlier, the DISM command isn’t available. Instead, you can download and run the System Update Readiness Tool from Microsoft and use it to scan your system for problems and attempt to fix them.”
    
    1 user thanked author for this post.
    
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    - February 4, 2017 at 4:40 pm #89418
      
      PhotM
      AskWoody Plus
      
      Yes BUT,
      
      When I was on W 7, the “System Readiness Tool” did not repair anything. That is one of the main reasons I went to W 8(it sure wasn’t the GUI).
      
      Also SFC is much more comprehensive on W 8 and higher and is still being enhanced on W 8.1 and especially W 10.
      
      Best Regards,
      
      Crysta
      
      --------------------------------------
      
      1. Tower Totals: 2xSSD ~512GB, 2xHHD 20 TB, Memory 32GB
      
      SSDs: 6xOS Partitions, 2xW8.1 Main & Test, 2x10.0 Test, Pro, x64
      
      CPU i7 2600 K, SandyBridge/CougarPoint, 4 cores, 8 Threads, 3.4 GHz
      Graphics Radeon RX 580, RX 580 ONLY Over Clocked
      More perishable
      
      2xMonitors Asus DVI, Sony 55" UHD TV HDMI
      
      1. NUC 5i7 2cores, 4 Thread, Memory 8GB, 3.1 GHz, M2SSD 140GB
      1xOS W8.1 Pro, NAS Dependent, Same Sony above.
      
      -----------------
      
      Reply | Quote
  - February 2, 2017 at 9:08 am #83358
    
    grumpy65867
    AskWoody Plus
    
    The MS Technet article on DISM is not long being maintained. See top yellow highlighted bar on article. It may not be the best source of information on DISM in the future.
    
    Reply | Quote
    - February 2, 2017 at 12:52 pm #83869
      
      Noel Carboni
      AskWoody_MVP
      
      Well, I originally wrote this against Windows 8 and posted it in the Windows 8 section of the site. That version of the OS isn’t changing that much either at this point. 🙂
      
      -Noel
      
      1 user thanked author for this post.
      
      WildBill
      
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  - February 2, 2017 at 9:53 am #83477
    
    PhotM
    AskWoody Plus
    
    I do this regularly(albeit with Scannow which actually does some repair) before and after major updates. It has saved me allot of grief and is one of the major reasons I left W 7 SP 1. Here is my script I C&P into Powershell(or CMD):
    
    ReagentC /Info
    sfc /scannow
    DISM /Online /Cleanup-Image /RestoreHealth
    DISM /Online /Cleanup-Image /AnalyzeComponentStore
    DISM /Online /Cleanup-Image /StartComponentCleanup
    DISM /Online /Cleanup-Image /AnalyzeComponentStore
    
    Best Regards,
    
    Crysta
    
    --------------------------------------
    
    1. Tower Totals: 2xSSD ~512GB, 2xHHD 20 TB, Memory 32GB
    
    SSDs: 6xOS Partitions, 2xW8.1 Main & Test, 2x10.0 Test, Pro, x64
    
    CPU i7 2600 K, SandyBridge/CougarPoint, 4 cores, 8 Threads, 3.4 GHz
    Graphics Radeon RX 580, RX 580 ONLY Over Clocked
    More perishable
    
    2xMonitors Asus DVI, Sony 55" UHD TV HDMI
    
    1. NUC 5i7 2cores, 4 Thread, Memory 8GB, 3.1 GHz, M2SSD 140GB
    1xOS W8.1 Pro, NAS Dependent, Same Sony above.
    
    -----------------
    
    2 users thanked author for this post.
    
    cmptrgy, HiFlyer
    
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  - February 2, 2017 at 10:35 am #83715
    
    b
    AskWoody MVP
    
    The self-healing feature is not called System Protection, which is the Restore Points storage in all versions from WinME to Win10: https://en.wikipedia.org/w/index.php?title=System_Protection&redirect=no
    
    Since Windows 2000, SFC has been part of Windows File Protection which does replace system files:
    https://en.wikipedia.org/wiki/Windows_File_Protection
    
    Windows 10 Pro version 21H2 build 19044.1149 + Microsoft 365 (group ASAP)
    
    1 user thanked author for this post.
    
    Noel Carboni
    
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    - February 2, 2017 at 12:45 pm #83868
      
      Noel Carboni
      AskWoody_MVP
      
      Thanks. That was a mental parity error – I’ve changed the wording.
      
      -Noel
      
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  - February 2, 2017 at 1:21 pm #83881
    
    ch100
    AskWoody_MVP
    
    Please be aware that users of Windows 7 Group B style of updating (without all Recommended patches) are likely to run into an issue breaking the functionality of SFC.
    If you require (and everyone does) SFC functionality, think again about your preferred style of updating.
    
    Reply | Quote
    - February 4, 2017 at 4:51 pm #89467
      
      PhotM
      AskWoody Plus
      
      All Updates do way more than One realizes or that MS will ever be prepared to Itemize.
      I would think that this will and does pertain especially to built in TOOLS.
      
      If a Patch/CU/Security/etc including a necessary Hotfix(not the special very specific ones) includes augmentation to A TOOL, without it the TOOL maybe broken…..
      
      Best Regards,
      
      Crysta
      
      --------------------------------------
      
      1. Tower Totals: 2xSSD ~512GB, 2xHHD 20 TB, Memory 32GB
      
      SSDs: 6xOS Partitions, 2xW8.1 Main & Test, 2x10.0 Test, Pro, x64
      
      CPU i7 2600 K, SandyBridge/CougarPoint, 4 cores, 8 Threads, 3.4 GHz
      Graphics Radeon RX 580, RX 580 ONLY Over Clocked
      More perishable
      
      2xMonitors Asus DVI, Sony 55" UHD TV HDMI
      
      1. NUC 5i7 2cores, 4 Thread, Memory 8GB, 3.1 GHz, M2SSD 140GB
      1xOS W8.1 Pro, NAS Dependent, Same Sony above.
      
      -----------------
      
      Reply | Quote
  - February 2, 2017 at 2:54 pm #83908
    
    Steve S.
    AskWoody Plus
    
    Thanks, Noel. I just ran sfc /verifyonly on my Win 7 Pro SP 1 that I’ve been running for years now. I have essentially been in Group B since the GWX debacle started in 2015. Results: 100% OK. Now I have some added “warm fuzzies”… 😉
    
    Win10 Pro x64 20H2, Win10 Home 20H2, Linux Mint + a cat with 'tortitude'.
    
    1 user thanked author for this post.
    
    Elly
    
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  - February 2, 2017 at 4:05 pm #84364
    
    WildBill
    AskWoody Plus
    
    I followed Noel’s instructions, doing VERIFYONLY 1st, then SCANNOW. SCANNOW indicated problems it couldn’t repair, so I ran DISM, then SCANNOW again. My PC was low on battery power & shut down on the last scan. I ran SCANNOW again & I have the warm fuzzies! This was the 1st time ever running SFC & DISM since I bought my Windows 8 (now 8.1) laptop 4 years ago.
    
    2 Machines for Now!
    #1: Windows 8.1, 64-bit, back in Group A.
    #2: Getting close to buying a refurbished Windows 10 64-bit, recently updated to v1909. Have broke the AC adapter cord going to the 8.1 machine, but before that, coaxed it into charging. Need to buy new adapter if wish to continue using it.
    Wild Bill Rides Again...
    
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  - February 2, 2017 at 5:18 pm #84649
    
    Canadian Tech
    AskWoody_MVP
    
    You will be interested to know that I just linked this web page to an answer to a question on the Microsoft Answers forum.
    
    CT
    
    1 user thanked author for this post.
    
    woody
    
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  - February 4, 2017 at 3:09 pm #89301
    
    Pepsiboy
    AskWoody Lounger
    
    Woody,
    
    When I try to run sfc (either verifyonly or scannow) all I get is aVERY brief flash of a DOS screen, then nothing else happens. Is there maybe something wrong going on here? Running Win 7 X64 SP1.
    
    I would attach a screen shot, but the flash of a DOS screen only lasts about 1/4 second.
    
    Thanks, in advance for any help or advice.
    
    Dave
    
    Reply | Quote
    - February 4, 2017 at 3:14 pm #89306
      
      Canadian Tech
      AskWoody_MVP
      
      Have you opened the Command prompt window using Run as administrator?
      
      CT
      
      Reply | Quote
    - February 5, 2017 at 10:59 am #90638
      
      WildBill
      AskWoody Plus
      
      Try running Windows PowerShell (admin) if it’s available on Windows 7. That’s where I ran SFC instead of the Command Prompt.
      
      2 Machines for Now!
      #1: Windows 8.1, 64-bit, back in Group A.
      #2: Getting close to buying a refurbished Windows 10 64-bit, recently updated to v1909. Have broke the AC adapter cord going to the 8.1 machine, but before that, coaxed it into charging. Need to buy new adapter if wish to continue using it.
      Wild Bill Rides Again...
      
      Reply | Quote
    - February 14, 2017 at 8:02 pm #94145
      
      PKCano
      Manager
      
      This was lost in the crash 2/13/2017:
      
      Start\All Programs\Accessories\
      RIGHT click on Command Prompt
      Choose “Run as Administrator”
      At the prompt in the black box that pops up type
      SFC /scannow
      
      1 user thanked author for this post.
      
      PhotM
      
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  - February 4, 2017 at 4:39 pm #89409
    
    Pepsiboy
    AskWoody Lounger
    
    Canadian Tech,
    
    Yes I have. The same thing happens there, too.
    
    Dave
    
    Reply | Quote
    - February 4, 2017 at 4:43 pm #89424
      
      Canadian Tech
      AskWoody_MVP
      
      Sorry, no idea. I have never seen that. Have you run a malware scanner? I use ADWcleaner:
      https://toolslib.net/downloads/viewdownload/1-adwcleaner/
      
      CT
      
      Reply | Quote
    - February 4, 2017 at 4:50 pm #89466
      
      PKCano
      Manager
      
      Somewhere I remember there was a KB that was supposed to repair SFC functionality. Don’t remember the particulars. Sept last year, I think, KB3181988. Seems like it didn’t come through WU, you had to download it from the Catalog. It can’t hurt anything to try. Be sure you get the right bitedness and the right version. http://www.catalog.update.microsoft.com/Search.aspx?q=3181988
      
      1 user thanked author for this post.
      
      Pepsiboy
      
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  - February 4, 2017 at 5:12 pm #89506
    
    Pepsiboy
    AskWoody Lounger
    
    PKCano,
    
    Thanks for the tip. I’ll try installing it later this evening and let you know what happens.
    
    Dave
    
    Reply | Quote
  - February 5, 2017 at 12:07 pm #90692
    
    PhotM
    AskWoody Plus
    
    WildBill wrote:
    
    Try running Windows PowerShell (admin) if it’s available on Windows 7. That’s where I ran SFC instead of the Command Prompt.
    
    Begging your Pardon Sir,
    
    But one needs AT LEAST CMD(Command Prompt) as Admin(elevation) to run SFC. I do usually use Powershell and it CAN be Installed on W 7. See the Following:
    
    Install and configure WMF 5.1 https://msdn.microsoft.com/en-us/powershell/wmf/5.1/install-configure
    
    Windows Management Framework (WMF) 5.1 Released | Windows PowerShell Blog https://blogs.msdn.microsoft.com/powershell/2017/01/19/windows-management-framework-wmf-5-1-released/
    
    WMF 5.1 Release Notes https://msdn.microsoft.com/en-us/powershell/wmf/5.1/release-notes
    
    PowerShell Magazine » Comparing commands between PowerShell versions http://www.powershellmagazine.com/2016/04/29/comparing-commands-between-powershell-versions/
    
    PowerShell Gallery | Home https://www.powershellgallery.com/
    
    Get Started with the PowerShell Gallery | MSDN https://msdn.microsoft.com/en-us/powershell/gallery/psgallery/psgallery_gettingstarted
    
    The PowerShell Gallery | MSDN https://msdn.microsoft.com/en-us/powershell/gallery/readme
    
    There are many more but one will find them through all of the above, for those whom are interested. Also keep a watch on @jsnover on Twitter the Father of Powershell.
    
    For clarification, I am still a novice BUT I do find PS and PS ISE(for the Module memory joggers) fascinating. However I do prefer GUI’s the most.
    
    Best Regards,
    
    Crysta
    
    --------------------------------------
    
    1. Tower Totals: 2xSSD ~512GB, 2xHHD 20 TB, Memory 32GB
    
    SSDs: 6xOS Partitions, 2xW8.1 Main & Test, 2x10.0 Test, Pro, x64
    
    CPU i7 2600 K, SandyBridge/CougarPoint, 4 cores, 8 Threads, 3.4 GHz
    Graphics Radeon RX 580, RX 580 ONLY Over Clocked
    More perishable
    
    2xMonitors Asus DVI, Sony 55" UHD TV HDMI
    
    1. NUC 5i7 2cores, 4 Thread, Memory 8GB, 3.1 GHz, M2SSD 140GB
    1xOS W8.1 Pro, NAS Dependent, Same Sony above.
    
    -----------------
    
    Reply | Quote
  - March 2, 2017 at 6:57 am #98216
    
    Pepsiboy
    AskWoody Lounger
    
    OK, I as going about it wrong. Now that I’m using the PROPER way to access it, it works perfectly.
    
    Thanks ot all for the tips.
    
    Dave
    
    Reply | Quote
  - May 28, 2017 at 5:59 pm #118480
    
    _Reassigned Account
    AskWoody Lounger
    
    Ran SFC /verifyonly on Win 7 SP1 x64 Pro. Got many errors, most of which point to all the files I deleted on one of my cleaning binges. Files are all the unused language files I do not need. Files located in various places in Windows and its sub-directories. Any cause for concern? Why must I keep the unused files of various languages? Did not delete various kbd files, too time consuming to figure out who’s who? Tnx.
    
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  - February 2, 2019 at 12:37 pm #319977
    
    bbearren
    AskWoody MVP
    
    FWIW, I never run any of the Windows tools in the “check” or “analyze” mode, I always run them in their repair mode. If there’s nothing wrong, I still get the “OK” from the tool, but if there is something wrong, I don’t have to re-launch the tool for a second run.
    
    If the Dism tool can’t effect repairs (which does happen on occasion) I use my installation media and run this command line:
    
    dism /online /cleanup-image /restorehealth /source:X:\repairsource\windows /limitaccess
    
    where X is the drive letter assigned by File Explorer when the media is plugged in.
    
    Create a fresh drive image before making system changes/Windows updates, in case you need to start over!
    "When you're troubleshooting, start with the simple and proceed to the complex."—M.O. Johns
    "Experience is what you get when you're looking for something else."—Sir Thomas Robert Deware
    Computer Specs
    
    1 user thanked author for this post.
    
    cmptrgy
    
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