CHKDSK, short for Check Disk, is a Windows system command line tool that verifies the file system integrity of a disk volume and fixes logical file system errors. It can also check the disk surface for bad sectors and mark them. It starts automatically during the boot when the system partition was marked dirty due to an unexpected shutdown, or bad sectors. Users can use it manually to check the disks or external flash drives for errors.
There are only a few switches available in CHKDSK you can use in Windows 7 systems. But it gets improved a lot with more options in Windows 8.1 and 10 since Microsoft improved the health model of NTFS as well as the way how it fixes the file system corruptions.
New options for NTFS volumes
The following switches are new in Windows 8 and carried over in Windows 10. They are for NTFS volumes only.
/scan – to run an online scan on the volume.
/forceofflinefix – to bypass all online repair and queue all defects for offline repair. Must be used with /scan.
/perf – to use more computer resource to perform a scan as fast as possible. This may have the negative performance impact on other tasks.
/spotfix – to perform a spot repair in offline mode.
/sdcclean – garbage collection.
/offlinescanandfix – to run an offline scan and fix on the volume.
New options for FAT/FAT32 and exFAT volumes
The following switches are new in Windows 10. They are for FAT/FAT32 and exFAT volumes only.
/freeorphanedchains – to free any orphaned cluster chains instead of recovering their contents.
/markclean – to mark the volume clean if no corruption was detected.
Note that the CHKDSK command needs to run in an elevated command prompt window. To check more details about other switches you can use with CHKDSK, run the following command.