A Win XPpro PC has a 72GB partitioned as drive C: (there is also a system restore partition of a few GB with no drive letter assigned).
My problem is that only about 23GB of the 72GB appears to be usable. Windows Explorer indicates a C: disk size of 72GB with 1.9GB free. However when you when you add up space taken by all directories and files it comes to just over 20GB.
Chkdsk confirms this as it reports a total disk space of about 72GB with 69GB used in about 82,000 files whereas indexed file space is 20GB in about 8,000 files. I have ran chkdsk /f but it completes without fixing the problem.
Urgent help in fixing this would be appreciated.