system file checker windows 7 download How to Repair Corrupted or Missing System Files in Windows 7/8/10? In this article, you are going to learn how to repair corrupted or missing system files in Windows 7/8/10 and restore your computer to previous good date. Details are in the following. By Ivy / Last update July 1, 2021. What is a system file? A system file is a more than important part of the system, as its name. It usually comes as part of the operating system which is used for its core operations. And it’s located in a system folder, such as, System32, which cannot be deleted even through the use of permissions. The aim is to protect system files from deletion mistakenly. The system files in Windows can make your computer run normally. If it’s corrupted or missing, your computer will not work properly. How to repair Windows if system files are corrupted or missing? Behind corrupted or missing system files, there are many reasons, such as sudden power drops, third-party programs, virus attacks, human error. Once you receive the error message that implies the system files is damaged, you can repair system files using cmd. The system file checker is the best way to start the troubleshooting. #1: System files integrity check and repair in Windows 7/8/10. For system file repair in Windows 7/8/10, you can try SFC (system file checker) command first. It can scan your computer and find the corrupted files, then restore the corrupted system files. Step 1. Type cmd in the search box and then select Run as administrator . Step 2. Type sfc /scannow in the command prompt and hit Enter. If your computer is unbootable, you still can repair system files using CD/DVD that come with your computer. You can boot from it, then directly press Shift +F10 to open command prompt and type the above command. #2: View SFC log and repair system files manually. After the sfc /scannow end, you may get there are still some unrepaired system files with error message like “Windows Resource Protection found corrupt files but was unable to fix some of them. Details are included in the CBS.Log %WinDir%\Logs\CBS\CBS.log. ” In this case, you should create a SFC log file with the CBS log file, then find the corrupt or missing Windows file and replace it with a good one. Create and View the SFC log file. Step 1. Open cmd as administrator, enter the following command in the pop-up window and then hit Enter . This operation can help you create a sfclogs.txt file on the desktop. findstr /c:”[SR]” %windir%\Logs\CBS\CBS.log >”%userprofile%\Desktop\sfclogs.txt” Step 2. Open the sfclogs.txt file, find the date and time entry for a file that could not be repaired. Note : the Sfcdetails.txt files use Date/Time SFC details format, thus you need to verify the date and time entries. Then, you can use it to find the unrepaired files. Repair damaged system files in Windows 7/8/10. 1. Find known good system files copies on another computer with the same version of the operating system. 2. Open CMD as administrator. 3. Type the following command to take ownership of the corrupted files and hit Enter to run it. takeown /f C:\Windows\System32\appraiser.dll. Note: C:\Windows\System32\appraiser.dll refers to the path and name of the corrupted system file. You should replace it. 4. Type the command below to give a full admin access to the corrupted files and then hit Enter . icaclsC:\Windows\System32\appraiser.dll /Grant Administrators:F. 5. Type the following command to replace the damaged system files and press Enter . copy D:\Files\appraiser.dll C:\Windows\System32\appraiser.dll. Note: D:\Files\appraiser.dll refers to the path and name of the known good file. You should replace it. 6. Type yes in the window and then Press Enter . 7. Type sfc /verifyonly command to check the integrity of all the system files and press Enter to move on. Wait until the process is 100% complete. Besides, you can use DISM command utility in Windows 8/10. It will automatically fix SFC Scannow not working as well as scan and repair system files in Windows 8/10. To run DISM command line, you need to open the command prompt as administrator and type the following command in the pop-up window and hit Enter. DISM /Online /Cleanup-Image /RestoreHealth. #3: Repair Windows 7/8/10 system files without CD. For the majority of users, the command line is a complicated thing. And it’s much easier to make a mistake. Thus, I recommend you a Windows built-in tool named System Restore. It’s easy to learn and operate. Step 1. Type system restore in the search box and select it. Step 2. Select one of the options as shown in the following and follow the wizard until the last step. For system restore point, you have two options, including Recommended restore , Choose a different restore point . If the recommended restore point is available, you’d better tick it. If not, you can tick Choose a different restore point and find the available restore point. Sometimes, you will find that there is no system restore points in Windows 7/8/10. Don’t worry about it. You can try the last two solutions to repair system files. #4: Repair Windows 7/8/10 system files without losing data. To make sure the security of your data, backup system is the best way. It will keep all your programs and files intact. And it’s very easy to operate, even for a beginner. A proper backup and restore software is very important for you if you want to backup system in simple ways. I recommend you free AOMEI Backupper Standard. To backup system, you can download free AOMEI Backupper Standard, install and launch it. Click Backup and System Backup to start the operation and then follow the wizard until the last step. One more things, you can backup to external hard drive, USB drive, cloud drive like Dropbox, Google Drive, etc. To restore your backup, you can open AOMEI Backupper, click Restore and select a system image first and then follow the wizard to finish the rest of steps. If your image is saved on the external hard drive, you need to create a bootable disk first. And then, use the bootable media to boot your computer and connect the drive containing your backup image. At last, restore image from external hard drive based on above wizard. What’s more, you can do system clone to HDD/SSD in advance. It’s simpler. You just need to replace the old drive with the cloned drive and boot from it. However, system clone is only available on the paid version, such as AOMEI Backupper Professional, AOMEI Backupper Server, etc. You need to upgrade the free version to a paid version based on the operating system you are using. #5: Repair system files with onekey recovery software. To create a system image backup from which you can repair corrupted system files, you can also try AOMEI OneKey Recovery. It enables you to save system image on a custom recovery partition and recover corrupted computer using the "F11" or "A" key during computer startup. All operations are quite simple. To backup system files, just choose OneKey System Backup after launching AOMEI OneKey Recovery. To perform system recovery when your computer boots normally, open the program and choose OneKey System Recovery . If your computer fails to boot, press F11 or A during startup (Legacy boot) or choose AOMEI OneKey Recovery in boot menu (UEFI boot) to launch the program and perform system restore from Windows PE. Wrapping things up. Reading here, you may already know how to repair missing system files in Windows 7/8/10. Compared with the previous 3 methods, I prefer the last two solutions. System file checker may not work all the time. If something goes wrong, you need to fix it. Also, system restore does not work forever. For example, if you upgrade Windows 7/8 to Windows 10, you will find system restore points gone. But a system backup or disk image will work all the time. It’s the most reliable way to repair system files in Windows 7/8/10. If you do not have a backup, you can download free AOMEI Backupper or AOMEI OneKey Recovery and then create a backup to get prepared for possible errors. How to Scan for (and Fix) Corrupt System Files in Windows. Walter Glenn is a former Editorial Director for How-To Geek and its sister sites. He has more than 30 years of experience in the computer industry and over 20 years as a technical writer and editor. He's written hundreds of articles for How-To Geek and edited thousands. He's authored or co-authored over 30 computer-related books in more than a dozen languages for publishers like Microsoft Press, O'Reilly, and Osborne/McGraw-Hill. He's also written hundreds of white papers, articles, user manuals, and courseware over the years. Read more. If your PC has been feeling buggy or having trouble during startup, it’s possible that Windows system files have become corrupt, gone missing, or even have been changed by a software installation somewhere along the line. Like most versions of Windows before it, Windows 10 includes a Command Prompt utility named Windows Resource Protection that will scan, verify, and fix system files. If your system is able to start, even in Safe Mode, you can run the utility right from Windows. If Windows won’t start, you can also run it from the Command Prompt available when you boot from your installation media into repair mode. To run this utility in Windows, you will need to open the Command Prompt in administrator mode. Right-click on the Start menu or press Windows+X on your keyboard, and choose “Command Prompt (Admin)” from the Administrative Tools menu. You can also just use this nifty keyboard shortcut. When you have the Command Prompt open in administrator mode, you can run the utility by using the following syntax: The most useful option is just to scan the whole system immediately, which will scan and attempt to repair any files that are changed or corrupted. You can do that with this command: Alternatively, you can use the command sfc /verifyonly to scan for problems, but not perform any repairs. You can also just scan or verify a particular file using the /scanfile= or /verifyfile= options along with the full path of the target file, like this: As we mentioned, this utility does exist for previous versions of Windows, but you may encounter slightly different options. You can always use the command sfc /? to get all supported options for your version of Windows. And just in case you’re wondering why Windows Resource Protection uses the command SFC, it’s because the utility used to be named System File Checker. How to use Windows 10's System File Checker (SFC) scannow command to fix problems. On Windows 10, when you start having issues starting your Windows laptop, random errors occur, or features don't work correctly, there is a good chance that some system files might be corrupted or missing for unknown reasons. Typically, you may experience problems with system files after installing a cumulative update, driver, or making installation changes manually. Whatever the reason it might be, if you come across any related issues, Windows 10 includes the System File Checker (SFC), a command-line tool designed to scan the integrity and restore missing or corrupted system files with working replacements. In this Windows 10 guide, we will walk you through the steps to use the System File Checker tool to repair damaged system files automatically or manually. How to repair Windows 10 with System File Checker. Warning: This is a friendly reminder that editing system files is risky, and it can cause irreversible damage to your installation if you don't do it correctly. It is recommended to make a temporary full backup of your PC before proceeding. To repair an installation of Windows 10 using the System File Checker tool, use these steps: Open Start . Search for Command Prompt , right-click the top result, and select the Run as administrator option. Type the following command to repair the Windows 10 system files and press Enter : Source: Windows Central. Confirm the command results: Windows Resource Protection did not find any integrity violations – indicates that the system does not have any corrupted or missing files. Windows Resource Protection could not perform the requested operation – indicates a problem during the scan, and an offline scan is required. Windows Resource Protection found corrupt files and successfully repaired them. Details are included in the CBS.Log %WinDir%\Logs\CBS\CBS.log – indicates that the tool detected problems and was able to fix them. Windows Resource Protection found corrupt files but was unable to fix some of them. Details are included in the CBS.Log %WinDir%\Logs\CBS\CBS.log – indicates you may need to repair the corrupted files manually. Once you complete the steps, the SFC command-line tool will scan, detect, and fix Windows 10 system file problems. When the tool detects an issue, it is recommended to run the command around three times to ensure that all the problems have been corrected properly. If you find problems running the tool, use this guide to use the Deployment Image Servicing and Management (DISM) tool to repair the local Windows 10 image files to allow SFC to complete successfully. System File Checker logs. To view the details stored in the CBS.Log file from an SFC scan, use these steps: Open Start . Search for Command Prompt , right-click the top result, and select the Run as administrator option. Type the following command and press Enter : findstr /c:"[SR]" %windir%\Logs\CBS\CBS.log > C:\sfclogs.txt" Source: Windows Central. Double-click the sfclogs.txt file to open it with the default text editor app. Source: Windows Central. After you complete the steps, the log file will reveal all the scanned system files and information for the unrepairable files. This option is only available when performing a scan within Windows 10, not when performing an offline scan with Command Prompt. How to repair Windows 10 with System File Checker offline. To repair Windows 10 using SFC with the offline option, use these steps: Open Settings . Click on Update & Security . Click on Recovery . Under the "Advanced startup" section, click the Restart now button. Source: Windows Central. Click on Troubleshoot . Source: Windows Central. Click on Advanced options . Source: Windows Central. Click on Command Prompt . (After selecting the option, the device will reboot.) Source: Windows Central. Type the following command to start the diskpart tool and press Enter : Type the following command to determine the location of the Windows and System Reserved partitions and press Enter : Confirm the current drive letter assignment for the System Reserved partition (the one close to 500MB) and Windows 10 partition, usually the volume with the largest size. Source: Windows Central. Type the following command to exit diskpart and press Enter : Type the following command to run the System File Checker offline and press Enter : sfc /scannow /offbootdir=F:\ /offwindir=C:\Windows. Source: Windows Central. In the command, we are using the /offboodir option to specify the drive letter of the System Reserved partition, which in this case is F . Also, the /offwindir option specifies the location of the Windows 10 files, which in this case is C:\Windows . Once you complete the steps, the command tool will fix any problems with system files on Windows 10, and the device will restart normally. How to repair Windows 10 manually without System File Checker. If the System File Checker cannot fix the damaged files, you may need to repair them manually. Determine corrupted system files. To find out which files need replacing on Windows 10, use these steps: Open Start . Search for Command Prompt , right-click the top result, and select the Run as administrator option. Type the following command and press Enter : findstr /c:"[SR]" %windir%\Logs\CBS\CBS.log > C:\sfclogs.txt" Source: Windows Central. Double-click the sfclogs.txt file to open it with the default text editor app. Source: Windows Central. After you complete the steps, the log file will reveal all the scanned system files and information for files that could not be repaired. While in the file, you can use the find option (Ctrl + F) in the text editor and look for the term: "Cannot repair member file" to identify the corrupted files that need replacing. Repair system files manually. You may be able to get good working files to replace in your installation from another device running the exact edition and version of Windows 10. If you do not know the location of the damaged file, you may need to perform an online search with the information available in the SFC log file. To repair damaged system files on Windows 10 manually, use these steps: Open Start . Search for Command Prompt , right-click the top result, and select the Run as administrator option. Type the following command to take ownership of the corrupted files and press Enter : takeown /f C:\PATH\TO\FILE. In the command, replace C:\PATH\TO\FILE with the actual path to the file that you are trying to fix. This example takes ownership of the "acproxy.dll" file: takeown /f C:\Windows\System32\acproxy.dll. Type the following command to grant full administrator access to the corrupted file and press Enter : icacls C:\PATH\TO\FILE /Grant Administrators:F. In the command, replace C:\PATH\TO\FILE with the actual path to the file that you are trying to fix. This example grants access to the "acproxy.dll" file: icacls C:\Windows\System32\acproxy.dll /Grant Administrators:F. Source: Windows Central. Type the following command to replace the corrupted files with a good-known version and press Enter : copy C:\PATH\TO\SOURCE\GOOD\FILE C:\PATH\TO\DESTINATION\BROKEN\FILE. In the command, replace C:\PATH\TO\SOURCE\GOOD\FILE with the path of the new file and C:\PATH\TO\DESTINATION\BROKEN\FILE with the path of the corrupted file. Source: Windows Central. Quick tip: If you get a message saying you cannot replace the file because another process is using it, then either find and terminate the process or perform this task offline. (See above steps). This example replaces the "acproxy.dll" file in the System32 folder: copy C:\Files\acproxy.dll C:\Windows\System32\acproxy.dll. Type the following command to verify the integrity of the Windows 10 system files and press Enter : Source: Windows Central. (Optional) Type the following command to verify the integrity of the replacement file and press Enter : In the command, replace C:\PATH\TO\REPLACED\FILE with the path of the file you replaced. This example verifies the integrity of the "acproxy.dll" file inside the System32 folder: Once you complete the steps, if the new files pass the integrity check, you have then resolved the problems with Windows 10. If you cannot repair the installation using the System File Checker, you may want to consider starting fresh with a clean installation of Windows 10. More Windows 10 resources. For more helpful articles, coverage, and answers to common questions about Windows 10, visit the following resources: Seven new HP X Series gaming monitors have been unveiled. Like flat and curved gaming monitors? Good news: HP has seven new models that have either just hit shelves or will be available for purchase in the next few months. Everything you need to know about AMD Radeon RX 6000 GPUs. AMD has unveiled its new lineup of Radeon RX 6000-series graphics cards, with three new pieces of hardware to look forward to. Here's what you need to know. Here's everything you need to know about the Activision Blizzard lawsuit. The lawsuit against Activision Blizzard alleging harassment, unfair pay, and a "frat boy" culture has rocked the video game industry. Here's everything you need to know about it, from the suit itself to the aftermath. Prepare for your next trip with the best travel routers. If you're going on a trip, you need a portable travel router that not only provides a fast connection, but offers a few more uses as well. Here's the travel routers that will make dealing with Wi-Fi on your tip a breeze. System file checker in windows 7. How to run system file checker in windows 7 home premium. I was suggested to do so to improve system performance and to solve windows lock-up problem. I was asked to run sfc/scannow in start menu search box but it didn't show any result. When I typed sfc in start menu search box and pressed enter , a cmd like window flashed and disappeared without asking anything. I am confused about what happened and what to do next. what is the purpose of sfc exactly. whether it runs and just disappears itself without notifying anything?? Run System File Checker To Repair Corrupted Or Missing Files In Windows 10. Is your Windows 10 PC is constantly crashing? Is your Windows 10 PC hangs a lot? Are you getting file missing or corrupted error in Windows 10? Run the built-in System File Checker tool to address these issues. System File Checker is a command line utility in Windows 10 that allows users to scan for missing and corrupted system files and repair them. The tool can be run either via Command Prompt or PowerShell. The System File Checker tool is helpful when your PC is not working as expected or showing file missing or corrupted errors. Run System File Checker in Windows 10. Complete the given below directions to run System File Checker tool in Windows 10. Step 1: Open Command Prompt as an administrator. You can do that by typing CMD in the Start/taskbar search field, right-clicking on Command Prompt entry and then clicking Run as administrator option. Click Yes button when you get the User Account Control prompt. Step 2: At the Command Prompt window, you need to execute the following DISM tool first before running the System File Checker tool. DISM.exe /Online /Cleanup-image /Restorehealth. The above command uses Windows Update to download files that are required to fix file corruptions. If you have disabled Windows Update or Windows Update is not working for some reason, please connect Windows 10 bootable media to your PC and then run the following command instead of the above one. If you don’t have the bootable media, download Windows 10 latest version ISO from Microsoft, mount the ISO file, and then execute the following command. DISM.exe /Online /Cleanup-Image /RestoreHealth /Source:C:\RepairSource\Windows /LimitAccess. In the above command, replace “C:\RepairSource\Windows” with the location of the resource source. Step 3: Next, type the following command and then press Enter key. sfc /scannow. The above command scans all protected system files and replaces corrupt files with a cached copy of the file present in a compressed folder located at System32\dllcache. The above command might take some time to process. So, be patient. Step 4: Once the system file checker completes its job, you will see one of the following messages: # Windows Resource Protection did not find any integrity violations. The above message indicates that there are no missing or corrupted system files on your PC. # Windows Resource Protection could not perform the requested operation. If you get this message, you might need to run the System File Checker in Safe mode again. We recommend running System File Checker once again in normal mode before trying that in safe mode. # Windows Resource Protection found corrupt files and successfully repaired them. You will get the above message when System File Checker detected corrupt or missing files and managed to repair them without any issues. # Windows Resource Protection found corrupt files but was unable to fix some of them.