A cyclic redundancy check (CRC) is a data verification method your computer uses to check the data on your disks (hard disks like your hard drive and optical disks like CDs and DVDs). A cyclic redundancy check error can be caused by several different issues: registry corruption, a cluttered hard disk, an unsuccessful program installation, or misconfigured files. Regardless of the specific cause, the cyclic redundancy check error is a serious one and must be addressed to avoid potential data loss or even a total system failure system. Luckily, there are a few simple ways to address this problem using (free) disk utility software. [1] X Research source
Repairing a CRC Error
- Open the CHKDSK utility and choose your scan type.
- Reboot the computer to start the scan.
- Open Command Prompt and type chkdsk /f [Drive Name] .
- Press enter and wait for the scan to complete.
- If this doesn’t fix the CRC error, use a third party disk scan utility instead.
Steps
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Access the CHKDSK utility. CHKDSK (or "check disk") is a built-in Windows utility that will scan and repair your drive's errors. It has the ability to find and repair a number of small errors or file corruptions that may be causing the cyclic redundancy error. Right click the drive you want to check, then click Properties->Tools. Under “Error Checking” click “Check Now”.
- If a CD or DVD is giving you this error it may be the result of a scratch or some dust. Try cleaning the disk with a soft cloth before anything else.
- Optical disk errors are often not repairable.
- If you get this error on a Mac (less common), first try the built-in Disk Utility and “Repair” the disk.
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Decide on a basic versus an advanced scan. Check boxes to indicate if you’d like to do a basic check and repair or an advanced one - the default is the basic scan.
- The basic scan should take around 15-20 minutes while the advanced scan may take hours. Make sure you’ve got the time set aside and don't disturb the computer once it begins.
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Reboot the computer to begin the scan. If scanning the main drive on your computer (the one you’re booted up on), CHKDSK will not be able to run immediately and will instead schedule the scan for the next time you reboot the computer.
- You can continue use the computer as normal at this point - restart when you know you have time for the full scan.
- If you suspect your hard disk is nearing the end of its life, get your data backed up before running the scan. Even if some data is already inaccessible, backup everything you can just in case.
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Use the alternate CHKDSK utility access. Sometimes running CHKDSK via right click makes it unable to run the scan and repair properly. If the first scan doesn't fix the issue, try the alternate method of running CHKDSK.
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Open the command prompt. Find the program "command prompt" under Accessories.
- Note that you must run CHKDSK commands as an administrator to have the necessary privileges to execute the scan.
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Type “chkdsk /f x:” into the command prompt. The letter “x” should be replaced with the letter name of the drive you’d like to run the scan on. Press enter.
- The previous step gives the command for the basic scan. For the advanced scan type "chkdsk /r x:” instead, where "x" is the letter name of the drive.
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Wait for the scan to complete. Once finished CHKDSK will give you a report and restart your computer. If CHKDSK is able to fix the issue this is all you need to do.
- If the /r repair seems to get stuck and never finish it (even if left overnight) is likely because you have many damaged files and CHKDSK will not be able to repair them. If this is the case, try the next method.
- Over time your hard disk may develop minor file corruptions and other small errors through a number of different means. CHKDSK can fix many small issues but cannot address more serious problems.
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Install a free disk utility. When CHKDSK isn't able to repair the issues with your hard disk, a 3rd party disk scan utility may be able to help. Popular options like HDDScan and SeaTools will provide an alternative to CHKDSK and may help solve the issue when CHKDSK fails.
- Many utilities offer different software versions for different operating systems (e.g. Mac OS vs PC/Windows)
- Be wary of "System cleaners" from disreputable sources. Look for established brands offering "disk utilities". [2] X Research source
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Open the utility and run the scan. Follow the instructions to run a scan on the drive that gave you the cyclic redundancy check error. The software should list all issues it finds in a short report.
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Repair all the issues. This process can run unattended, overnight. It's important to let the repairs run to completion, and depending on the state of your hard disk this repair could take more than 2 hours.
- If the repairs still aren't completed after the scan has run for more than 4 hours, this is a sign of a failing hard drive. Cancel the scan and backup whatever data you can.
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Rescan your computer. This should only take a few minutes and will ensure that there are now no errors.
Expert Q&A
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QuestionWhat are other ways to fix this?Michael Thompson-Brown is a Cybersecurity Expert based in Portland, Maine. He is the owner and founder of PCRescue!, a company that provides cybersecurity and data management solutions to small businesses and individuals. Michael has over 25 years of experience in the IT industry and is a certified ethical hacker. He is passionate about helping clients protect their data and systems from malicious attacks and helping them optimize their online presence and reach. He received a Master’s degree in Cybersecurity and Information Assurance from Western Governors University, and a Bachelor’s degree in Business Administration from the University of Phoenix.As a last resort, you can format your drive. Begin by backing up your data to ensure no important information is lost, as this method wipes out the entire drive. Then, locate the problematic drive in File Explorer, right-click it, and select "Format." Choose the desired file system format and allocation unit size, then opt for a quick format if preferred. Confirm the erasure of all data on the drive and wait for the process to complete. Once finished, the drive should be free from CRC errors. Remember to restore any essential data from backups.
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QuestionInstallation of operating system is taking too much time. Why?Community AnswerThe installation process is probably hung up on a certain line of code. If there is a way to cancel, do that and try installing again. Otherwise, you may have to wait until it is done. Also, try unplugging unnecessary devices, e.g., USB mouse, extra flash drives, etc.
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QuestionI am trying to download a game from a disk to my PC. While setting up the game, it gives me this kind of error again and again. What should I do?Community AnswerThis may be a case of a scratched or corrupted (unreadable) disk. I would try to source the game from another disk or an on-line alternative to make sure.
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Tips
- CDs and DVDs may throw CRC errors if there is a smudge or scratch on the disk. Try cleaning the disk with a soft cloth or buying a scratch repair kit if the disc itself is important to youThanks
Warnings
- With hard drives, CRC errors can be an indicator of impending hard drive failure. Always back up your most important dataThanks
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