IMO, chkdsk /r is the most meaningful tool provided within XP for repair/maintenance purposes. There are various types of chkdsk commands that can be used, but the most complete/thorough check is accomplished when running chkdsk /r command or the equivalent. Chkdsk /r results in a 5-stage process whereas all others will result in lesser checks.Phase 1: Checking files
During its first pass, Chkdsk examines each file record segment in the volume's master file table (MFT) and examines it for internal consistency. At the end of this phase, Chkdsk has identified the space that is in use and the space that is available, both within the MFT and on the volume as a whole. Phase 2: Checking indexes (directories)
During this pass, Chkdsk examines each directory that is on the volume, checking for internal consistency and verifying that every file and directory that is represented by a file record segment in the MFT is referenced by at least one directory. Chkdsk confirms that every file or subdirectory that is referenced in a directory actually exists as a valid file record segment in the MFT and also checks for circular directory references. Finally, Chkdsk confirms that the time stamps and file size information for the files are up-to-date in the directory listings for those files. Phase 3: Checking security descriptors
During this phase, Chkdsk examines each security descriptor that is associated with files or directories on the volume. Security descriptors contain information about ownership of a file or directory, about NTFS permissions for the file or directory, and about auditing for the file or directory. Phases 4 and 5: Checking sectors (optional)
If the /R switch is in effect, Chkdsk runs two more passes to look for bad sectors. During stage 4, Chkdsk verifies all clusters in use
; during stage 5, Chkdsk verifies unused clusters
.Interrupting the Chkdsk process when it is used with the /F or the /R switch is not recommended
. The integrity of the disk can be compromised by stopping the process. Do not start a scan if a thunderstorm is expected and you are subject to power failures. I also strongly advise an uninterruptible power supply to guard against short-term power outages or fluctuations.