Windows 7 Forums
Welcome to Windows 7 Forums. Our forum is dedicated to helping you find support and solutions for any problems regarding your Windows 7 PC be it Dell, HP, Acer, Asus or a custom build. We also provide an extensive Windows 7 tutorial section that covers a wide range of tips and tricks.


Windows 7: SFC /SCANNOW Command - System File Checker



SFC /SCANNOW Command - System File Checker

How to Repair Windows 7 System Files with System File Checker
Published by Brink
09 Jan 2009
Published by
How to Repair Windows 7 System Files with System File Checker


information   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   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

warning   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.





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   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" (right click -> Run as administrator), 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.

Name:  Command-1.jpg
Views: 881693
Size:  67.3 KB
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   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.

Name:  Finished.jpg
Views: 861155
Size:  80.1 KB
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   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.
Code:
findstr /c:"[SR]" %windir%\Logs\CBS\CBS.log >"%userprofile%\Desktop\sfcdetails.txt"
Name:  sfcdetails.jpg
Views: 789600
Size:  37.1 KB
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   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






18 Jan 2009   #1
shadowminx69

Windows 7 Build 7000
 
 

would it be a bad Idea to make a task to run this each night? not sure if it would be a good Idea or not. Hit me back


My System SpecsSystem Spec
18 Jan 2009   #2
Romulinx2

Win7 Ultimate x64 on Desktop / Win7 Ultimate x86 on laptop / Win7 x86 Starter on Netbook
 
 

Thanks, I forgot about this. I used to use it in early editions of windows. Run it and sorted some errors.
My System SpecsSystem Spec
18 Jan 2009   #3
darkassain

Windows 7 Ult x64(x2), HomePrem x32(x4), Server 08 (+VM), 08 R2 (VM) , SuSe 11.2 (VM), XP 32 (VM)
 
 

Quote   Quote: Originally Posted by shadowminx69 View Post
would it be a bad Idea to make a task to run this each night? not sure if it would be a good Idea or not. Hit me back
you shouldnt have any problem with it...
My System SpecsSystem Spec
.


18 Jan 2009   #4
Brink
Microsoft MVP

64-bit Windows 8.1 Enterprise
 
 

Quote   Quote: Originally Posted by Romulinx2 View Post
Thanks, I forgot about this. I used to use it in early editions of windows. Run it and sorted some errors.
You're welcome Romulinx2.

Shawn
My System SpecsSystem Spec
07 Feb 2009   #5
thunder2008

Windows 7 RC 7100
 
 

Very useful information running the sfc atm, thank you for this thread.
My System SpecsSystem Spec
07 Feb 2009   #6
Brink
Microsoft MVP

64-bit Windows 8.1 Enterprise
 
 

You're welcome Thunder2008.
My System SpecsSystem Spec
01 Mar 2009   #7
anykey

Dual boot XP Pro and Seven/7127
 
 

Good to see this again.
Thanks for the reminder.

Didn't you used to put some letters/codes as a suffix, something such as /* or /?. This was to fix things.
My System SpecsSystem Spec
01 Mar 2009   #8
Brink
Microsoft MVP

64-bit Windows 8.1 Enterprise
 
 

Hello Anykey,

You could type sfc /? in the elevated command prompt for a complete list of sfc commands to use, but sfc /scannow is the best option to scan and repair all protected system files command. No other suffixes that I know of though.

Name:  sfc_list.jpg
Views: 786440
Size:  144.6 KB


My System SpecsSystem Spec
01 Mar 2009   #9
anykey

Dual boot XP Pro and Seven/7127
 
 

Thanks Brink, perhaps I am thinking of the old chkdsk.
I was always taught to do it something like this:

chkdsk /f /r /v /e
My System SpecsSystem Spec
Comment

 SFC /SCANNOW Command - System File Checker




Tutorial Tools



Similar help and support threads for2: SFC /SCANNOW Command - System File Checker
Windows 7 Tutorial Category
system file checker Performance & Maintenance
System File Checker (sfc), Options? Performance & Maintenance
System File Checker Help Please Performance & Maintenance
Solved New System File Checker : sfc /scannow tutorial Chillout Room
System File Checker did not fix all problems Performance & Maintenance
System File Checker BSOD Help and Support

Our Sites

Site Links

About Us

Find Us

Windows 7 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 7" and related materials are trademarks of Microsoft Corp.

Designer Media Ltd

All times are GMT -5. The time now is 11:42 AM.
Twitter Facebook Google+



Windows 7 Forums

Seven Forums Android App Seven Forums IOS App