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

 

[Brink]

I am following your instruction by going to start, all programs, accessories, right clicking command prompt and selecting "run as administrator". It takes me to a regular command prompt..C:\Users\Daniel>...according to your instructions...is should read...C:\Windows\system32...what am I doing wrong?

Hello Krash, and welcome to Seven Forums.

If you have UAC notifications turned on to default or above, did you get a UAC prompt after clicking on Run as administrator? If, not then it sounds like you may have clicked on Open by mistake instead of Run as administrator.

 

[sluice]

Windows 7 SFC /Scannow

I'm running Windows 7 Ultimate SP1. I'm trying to run sfc /scannow to fix a problem, but I always get "Windows Resource Protection could not start the repair service". I therefore have restarted from a Win 7 boot disk and selected Repair and the Command prompt option. I run del \windows\winsxs\pending.xml first and then sfc /scannow /offbootdir=c:\ /offwindir=c:\windows. I still get "Windows Resource Protection could not start the repair service". What should I try next?

 

[Brink]

Hello Sluice,

Double check to make sure that the Windows Modules Installer service is set to be enabled and Manual, then try to run SFC again to see if that may help.

http://www.sevenforums.com/tutorials/2495-services-start-disable.html

Hope this helps,
Shawn

 

[sluice]

Windows 7 SFC/SCANNOW

Hi Shawn,
Windows Modules Installer service is enabled and Manual and not started. SFC/scannow still gives the same error.

 

[Brink]

Sluice,

Try METHOD TWO in the tutorial below to help make sure that you have the correct drive letter while running SFC at boot to see if it will run this time around. This Windows drive is not always C at boot.

http://www.sevenforums.com/tutorials/139810-sfc-scannow-run-command-prompt-boot.html

 

[krash55918]

problem fixed

I was able to figure out what was going wrong...I had my security almost turned off,....thank you for all your help....krash

 

[Brink]

That's great news Krash. I'm happy to hear that you got it sorted.

 

[sluice]

Win 7 SFC /Scannow

Sluice,

Try METHOD TWO in the tutorial below to help make sure that you have the correct drive letter while running SFC at boot to see if it will run this time around. This Windows drive is not always C at boot.

http://www.sevenforums.com/tutorials/139810-sfc-scannow-run-command-prompt-boot.html

My boot/Windows drives are both C:. My D: drive is data only and is a separate physical drive.

 

[Brink]

It showed these drive letter at boot using the diskpart command with "list volume"?

 

[sluice]

Thanks all for your suggestions. I have done a Repair Installed Windows 7 SP1 as per http://www.sevenforums.com/tutorials/3413-repair-install.html to ensure that everything is updated and working correctly. I still can't do an sfc /scannow from a DOS prompt in Windows; the same reply comes back. I have checked that Windows Module Installer is Manual and Started.

 

[wireman642]

Hello,
I've followed the instructions posted here a few times without success.
I was wondering if you could take a look at the log attached.
I've attempted to replace both the main and stored locations at separate times:
C:\windows\SysWOW64\autochk.exe
C:\windows\winsxs\amd64_microsoft-windows-autochk_31bf3856ad364e35_6.1.7601.17514_none_4019f2b8d860ad30\autochk.exe

Am I missing something or do you think I should just run a repair install?
Thanks ahead of time

 

[Brink]

Hello Wireman, and welcome to Seven Forums.

The screenshot below shows all 4 different locations that this file is located. You might see if replacing the file from and to the same locations from either your installation disc or another computer may help. You'll notice the the size of the file is different.

 

[wireman642]

I've been trying to fix that error for 3 months and you nailed it.
It turns out that the winsxs 32-bit autochk (size 653Kb in the photo) was the problem.
Thank you Brink

 

[Brink]

That's great news. You're most welcome. I'm not sure why they would be different either, but I suppose they have their reason.

 

[cement406]

I ran the sfc /scannow command on my Windows 7 Home Premium PC and obtained the following text file, after parsing out the relevant parts of the CBS.log file. According to the attached file, the files "adojavas.inc" and "adcjavas.inc" do not exist on my computer. But I can see them on my computer when doing a search. Any suggestions on how to remedy the error messages in the attached file?

 

[Brink]

Hello Cement, and welcome to Seven Forums.

You could do a full search with "Computer" selected in Windows Explorer to find all locations that they are at. If you are not having any issues from this, then I wouldn't worry about it. If you are, then you could use the yellow TIP box at the bottom of OPTION THREE to replace them at those locations from the same locations on your retail installation disc.

 

[JonathanV]

Do I need to logged on as administrator to do this tutorial?

 

[Brink]

Yep, as per step 1 to open an elevated command prompt.

 

[JonathanV]

Will this work if using normal command prompt (not elevated)?

 

[Brink]

Nope, must be elevated as in the tutorial.