The problem is that I am unable to set boot time disk scanning. whenever I want to set through disk checking utility or with commandline "chkdsk" utility the system throws an error messaging stating that chkdsk has encountered error. Although it is running perfectly in windows for only scanning purpose. All this start after I have set a boot time defragmentation with Diskeeper 9 which don't complete at next boot up. Now Diskeeper is continuosly throwing error that there is disk check schedule and can't run defragmentation (which is on smart schedule) until disk check is complete. Please help me out. Thanks in advance for your valuable help.