I've been using version 1.19.192 without success so I uninstalled it. The settings.ini file was not found but I removed the Defraggler.exe.[1_18_185][2010-05-10_11-40].txt file from the directory. Then I removed that directory.
I reinstalled version 1.19.192 and ran Check Drive for Errors. The test was unable to complete successfully and the program offered to run CHKDSK. That, of course, fails. Defraggler is using it.
I restarted Windows to run CHKDSK at startup. It completed checking the disk. The Event Viewer shows, in part, the following report for winlogon:
Cleaning up minor inconsistencies on the drive.
Cleaning up 6695 unused index entries from index $SII of file 0x9.
Cleaning up 6695 unused index entries from index $SDH of file 0x9.
Cleaning up 6695 unused security descriptors.
CHKDSK is verifying Usn Journal...
Usn Journal verification completed.
CHKDSK discovered free space marked as allocated in the
master file table (MFT) bitmap.
Windows has made corrections to the file system.
I ran Defraggler again to defragment the drive. Again it hangs at 89% complete with 59 fragmented files, 137 total fragments and 1% fragmentation. There is no activity on the sector display.