"SCANREG /FIX" command is not working properly

hi wilders!

hope I have choosen right section to post my problem...

Problem: "SCANREG /FIX" command is not working properly and stops in midway.
[ o/s = win 98se]

**** let me specify at what step it stops:
______________monitor display during scanreg/fix________

Repairing c:\windows\system.dat


v~ Looking for valid system registry keys
>> Checking system registry structure [... at this step it stops and screen stays as it is]
Rebuilding system registry


0% complete
__________________________________________________

please help!