SFC /SCANNOW Command - System File Checker

How to Repair Windows 7 System Files with System File Checker​

   Information

The sfc /scannow command (System File Checker) scans the integrity of all protected Windows 7 system files and replaces incorrect corrupted, changed/modified, or damaged versions with the correct versions if possible.

   Tip

If you get the Windows Resource Protection Could Not Start the Repair Service error when trying to run SFC, then make sure that the Windows Modules Installer service is enabled, click on Start, and set to Manual.

Services - Start or Disable

OR

Copy and paste the command below in the elevated command prompt, and press Enter. After the Windows Modules Installer service has started, try running the SFC command again

net start trustedinstaller

   Note

The KB3022345, KB3035583, and KB3068708 updates will cause SFC to give you a false mismatch message in SFC for files related to these updates.

You can safely ignore these results in your SFC details since it will not affect SFC from being able to repair other system files.

   Warning

Be aware that if you have modified your system files as in theming explorer/system files, running sfc /scannow will revert the system files such as explorer.exe back to it's default state. Make the appropriate backups of your system files that you have modified for theming if you wish to save them before running sfc /scannow.

:note: For the updated Windows 10 tutorial, please see - SFC Command - Run in Windows 10 - Windows 10 Tutorials

CONTENTS:

• Option One: To Run the SFC /SCANNOW Command at Boot
• Option Two: To Run the SFC /SCANNOW Command in Windows 7
• Option Three: How to See and Read Only the "SFC" Scan Results from the CBS.LOG

OPTION ONE

To Run the SFC /SCANNOW Command at Boot

1. For how, see METHOD TWO at this link: SFC /SCANNOW : Run in Command Prompt at Boot

   Note

Using OPTION TWO below is recommended if able.

If you would like to get help with your SFC issue, then be sure to upload and attach your sfcdetails.txt file from OPTION THREE below in your post.

OPTION TWO

To Run the SFC /SCANNOW Command in Windows 7

1. Open an elevated command prompt or an elevated PowerShell, and do step 2 or 3 below for what type of scan you would like to run.


2. To Scan and Repair System Files
NOTE: Scans the integrity of all protected system files and repairs the system files if needed. Please see red WARNING box at the top of this tutorial.
A) In the elevated command prompt, type sfc /scannow, press Enter, and go to step 4 below. (see screenshot below)
NOTE: This may take a little bit to finish.


3. To Only Verify if the System Files are Corrupted
NOTE: Scans and only verifies the integrity of all proteced system files only. This command will not change your system files as in the red WARNING box at the top of this tutorial.
A) In the elevated command prompt, type sfc /verifyonly, press Enter, and go to step 4 below.
4. When the scan is complete, hopefully you will see all is ok like the screenshot below.

   Note

• If SFC could not fix something, then run the command again to see if it may be able to the next time. Sometimes it may take running the sfc /scannow command 3 or more times to completely fix everything that it's able to.
• If not, then download and run the 32-bit (x86) or 64-bit (x64) System Update Readiness Tool for your same installed 32-bit or 64-bit Windows 7, restart the PC afterwards, and try the sfc /scannow command again.
• If still not, then try using OPTION ONE above to run the sfc /scannow command at boot.
• If still not, then you can attempt to run a System Restore using a restore point dated before the bad file occured to fix it. You may need to repeat doing a System Restore until you find a older restore point that may work.
• If still not, then you can use the steps in the TIP box in the OPTION THREE section below to manually replace the files that SFC could not fix if there are not to many fix.
• If there are to many files to manually fix, or you prefer not to use OPTION THREE below, then you could do a repair install without losing anything.

If you would like to get help with your SFC issue, then be sure to upload and attach your sfcdetails.txt file from OPTION THREE below in your post.

5. When done, close the elevated command prompt.

OPTION THREE

How to See and Read Only the "SFC" Scan Results from the CBS.LOG

   Note

When SFC runs, it logs it's actions into the C:\Windows\Logs\CBS\CBS.log. The steps in this option will show you how to see only the specific SFC entries with the [SR] tags in this CBS.log. This can be helpful to show you what files SFC could not fix automatically if you wanted to try and manually replace them.

1. Open an "elevated command prompt" (right click -> Run as administrator).

2. In the elevated command prompt, copy and paste the command below, and press Enter. (See screenshot below)
NOTE: This will place a sfcdetails.txt file on your desktop with only the SFC scan result details from the CBS.LOG in it.

findstr /c:"[SR]" %windir%\Logs\CBS\CBS.log >"%userprofile%\Desktop\sfcdetails.txt"

3. Close the elevated command prompt.

4. Open the sfcdetails.txt file on your desktop to see the SFC scan details in the CBS.LOG.

5. You can safely delete the sfcdetails.txt file afterwards if you like.

   Tip

If you need to replace a corrupted system file that SFC cannot fix, then this will show you how to by extracting a new copy directly from your Windows 7 installation DVD.

Extract Files from Windows 7 Installation DVD

That's it,
Shawn

Related Tutorials

---

• How to Run the System File Checker in a Command Prompt at Boot
• How to Do a System Restore in Windows 7
• How to Do a Repair Install to Fix Windows 7
• How to Run Disk Check in Windows 7
• How to See Windows 7 Reliability and Problem History with Reliability Monitor
• How to Extract Files from the Windows 7 Installation DVD
• How to Troubleshoot a Problem by Performing a Clean Startup in Windows 7 or Vista

 

[AddRAM]

Is that part of a windows printer or his local printer ?

Why would sfc be concerned with his local printer files ?

I can`t get my sfc to go past 9% would a repair install fix it ?

It`s really no big deal as this OS is running perfectly.

I have a new Intel SSD arriving tomorrow and I`m reinstalling on that.

 

[Brink]

Hey Brian,

Not sure other than SFC couldn't repair that one system file of his.

What happens at 9%? Does it error out, or....? You might see if SFC may be able to finish if ran at boot instead though.

Nice choice of SSD.

 

[Atom222]

Hi Shawn, You're a life saver! A gazillion thanks to you and the System Update Readiness Tool. After it did the scanning, a report named CheckSUR.log was generated and it clearly stated that the 4 errors mentioned in your post were found and fixed. A subsequent SFC scan confirmed that there were no more "integrity violations". A real happy ending! One more thing, does it mean that I'll have to run the System Update Readiness Tool again should I encounter any similar problems in the future? Am I right to think that it just did a scan and repaired the errors and that it didn't actually install any application onto my laptop?

 

[Brink]

Great news Atom.

 

[paulderdash]

Hi
I have run a sfcscannow and the sfcscannow.txt from the CBS.log shows the following (relevant) entries, which it can't fix:

2014-01-11 18:30:40, Info CSI 0000012c [SR] Cannot repair member file [l:22{11}]"NapiNSP.dll" of Microsoft-Windows-Naming-Provider-Infrastructure, Version = 6.1.7600.16385, pA = PROCESSOR_ARCHITECTURE_AMD64 (9), Culture neutral, VersionScope = 1 nonSxS, PublicKeyToken = {l:8 b:31bf3856ad364e35}, Type neutral, TypeName neutral, PublicKey neutral in the store, hash mismatch
2014-01-11 18:30:42, Info CSI 0000012e [SR] Cannot repair member file [l:22{11}]"NapiNSP.dll" of Microsoft-Windows-Naming-Provider-Infrastructure, Version = 6.1.7600.16385, pA = PROCESSOR_ARCHITECTURE_AMD64 (9), Culture neutral, VersionScope = 1 nonSxS, PublicKeyToken = {l:8 b:31bf3856ad364e35}, Type neutral, TypeName neutral, PublicKey neutral in the store, hash mismatch
2014-01-11 18:30:42, Info CSI 0000012f [SR] This component was referenced by [l:202{101}]"Microsoft-Windows-Foundation-Package~31bf3856ad364e35~amd64~~6.1.7601.17514.WindowsFoundationDelivery"
2014-01-11 18:30:42, Info CSI 00000132 [SR] Could not reproject corrupted file [ml:520{260},l:46{23}]"\??\C:\Windows\System32"\[l:22{11}]"NapiNSP.dll"; source file in store is also corrupted

and

2014-01-11 18:33:01, Info CSI 0000016e [SR] Cannot repair member file [l:24{12}]"snmptrap.exe" of Microsoft-Windows-SNMP-Trap-Service, Version = 6.1.7600.16385, pA = PROCESSOR_ARCHITECTURE_AMD64 (9), Culture neutral, VersionScope = 1 nonSxS, PublicKeyToken = {l:8 b:31bf3856ad364e35}, Type neutral, TypeName neutral, PublicKey neutral in the store, hash mismatch
2014-01-11 18:33:04, Info CSI 00000170 [SR] Cannot repair member file [l:24{12}]"snmptrap.exe" of Microsoft-Windows-SNMP-Trap-Service, Version = 6.1.7600.16385, pA = PROCESSOR_ARCHITECTURE_AMD64 (9), Culture neutral, VersionScope = 1 nonSxS, PublicKeyToken = {l:8 b:31bf3856ad364e35}, Type neutral, TypeName neutral, PublicKey neutral in the store, hash mismatch
2014-01-11 18:33:04, Info CSI 00000171 [SR] This component was referenced by [l:202{101}]"Microsoft-Windows-Foundation-Package~31bf3856ad364e35~amd64~~6.1.7601.17514.WindowsFoundationDelivery"
2014-01-11 18:33:04, Info CSI 00000174 [SR] Could not reproject corrupted file [ml:520{260},l:46{23}]"\??\C:\Windows\System32"\[l:24{12}]"snmptrap.exe"; source file in store is also corrupted

Please will you let me know which option I should best pursue to fix this?

I should add that these errors do not seem to be causing a problem ...

Thanks in advance ...

 

[Brink]

Hello Paul, and welcome to Seven Forums.

If you haven't already, go ahead and go through the listed items in the blue Note box under step 4 in OPTION TWO to see if SFC may be able to repair the files afterwards.

 

[paulderdash]

Hi Shawn

I have unsuccessfully tried sfcscannow, and the System Update Readiness Tool, so I will try 'command at boot' option next (hesitantly, as I have no noticeable problems!).

A question: Option 1 specifically mentions Method 2. I am not dual booting so am I OK to do Method 1?

Rgds - Paul

 

[Brink]

Hello Paul,

The dual boot part doesn't matter for this. It's just that I prefer Method 2 since it includes a check to make sure you are using the correct drive letter to run SFC. Drive letters are not always the same at boot as they are in Windows.

It wouldn't hurt to do a full scan of your system with Windows Defender Offline at boot as well just to be safe.

 

[paulderdash]

Ran Windows Defender Offline - no problems.

After discovering that my optical drive was faulty and having it replaced by Dell (within 24 hours in South Africa btw which is not too shabby) I ran Option 1 Method 2 twice (from my Recovery Partition E: to Windows OS C. Both times got the message 'Windows Resource Protection found corrupt files but was unable to fix some of them'.

Reran sfc /verifyonly and exactly the same problems exist. I suppose I will have to extract files from my OEM re-installation DVD?

So far I haven't experienced any problems (that I know of) due this corrupt .exe and .dll so I wonder if it's worth it ...

 

[Brink]

If you're not having any issues because of them, then I wouldn't worry about it to much.

If you like, you could download and run the 64-bit (x64) System Update Readiness Tool for your same installed 64-bit Windows 7, restart the PC afterwards, and try the sfc /scannow command again.

 

[paulderdash]

Oops - forgot to mention ... had done that already!

Thanks for your help Shawn. When I have some idle moments, I'll try the last step of extracting the files from the installation DVD.

 

[Brink]

Anytime. I hope it goes smoothly.

 

[paulderdash]

P.S. Failing all else - your opinion, could this work? Win7?s no-reformat, nondestructive reinstall

 

[Brink]

Yes, a repair install should be able to fix them without losing anything. However, if you're not having any issues, then that wouldn't really be necessary to do unless you just wanted to.

How to Do a Repair Install to Fix Windows 7

 

[windowsfreak]

Thanks people, I downloaded the new Mavericks theme pack and I couldn't restore my laptop to the original uxtheme files that the patcher it came with patched on my own. The SFC Scannow feature of Windows 7 has REALLY helped by ending my search. I have it running now. Thanks a lot!

 

[giovy]

Hello!
There are some files system in my machine running W7 Ultimate Service Pack 1 (32bit) which cannot be fixed by the SFC Scannow tool.

I enclose the CBS logs for further investigation (I've used this magic FREE & PORTABLE app for that: Read and analyze Cbs.log Free Download)

It shouldn't be a serious problem though, because my system is running smoothly except for 2 key functionalities:

1) Windows Update function
2) Restore Point function

As for the first issue, whenever I launch Windows Update it fails to show me if any possible update is required.
All warning messages refer to error codes related to the impossibility to gain access on Microsoft servers.
Please note that I run, as a PC Tune Up tool an excellent free Chinese tool called "Baidu PC Faster", which does have a module called "Smart Update" that actually replace the Windows Update function.Have you ever heard about it before?
According to its developer this function is better than the Windows Update one, since it gives you smarter updates for you system: in fact it has found about 20 security patches needed to be applied on my system missed by Windows Updates itself. However, once unchecking their own update funcionality, Windows Update still doesn't work at all (getting the same error codes as mentioned above).
What do you make of it? Is in your view their Update function really better than the Windows one?
And why the heck is Windows Update not working even when their function is disabled?
Could it be blocked by their service running in the background (Baidu PC Faster Service 4.0.0.0) or is this problem related to some missing files system that the SFC Scannow tool cannot repair??
Please note than I've also tried to disable their service mentioned above, by using the freeware "ToolwizCare", but unfortunately my attempt was unsuccessful since Toolwizcare failed to do that.

As far as the second issue is concerned, whenever I try to roll back my system to a previous restore point, Windows and any other third party tool are not able to do that, even in SAFE MODE: again, in your view, what could be the cause of it? Could it be related to a missing file system as well (see attached CBS logs for more details)?
If so, how can I fix this annoying issue without being forced to reinstall my system from scratch?

Can't wait to hear from you.

 

[Brink]

Hello giovy,

If you have not already, you might see if doing a system restore at boot may work instead.

Hope this helps for now,
Shawn

 

[giovy]

Hello Brink!
Many thanks for your reply. I'll try to do a system restore at boot as soon as I can.
Unfortunately I deleted most of my previous restore points (the oldest one) in order to freeup disk space, so I'm not sure that this will solve the other issues I mentioned above.
Wait for your feedback about my cbs logs.

 

[Brink]

Looking at your CBS log, SFC only shows your Music, Photo, and Video samples files as missing and unable to repair.

These files are nothing to worry about though since they are only the default samples included in Windows.

 

[giovy]

Ok that's great...so what could be the cause of the 2 issues mentioned above?