NT Server 4.0 Boot problem

I have NT Server 4.0 updated to service pack 6.0a. Build 1381. This is the primary domain controller. I do have 2 backup domain controllers that work good.
When booting I get this error. "A kernel file is missing from the disk. Insert a system diskand restart the system".
If I put in a bootable floppy everything works good. I have followed everything the article in the MS knowledge base says to do. (Move the NTLDR file to a different location on the disk, Use a defrag utility, and so on.)Theonly thing I cannot do that they say is download a file called Bcupdate.exe which is suppose to update the the boot code. I cannot locate this file anywhere and am told that this is a file that MS was developing and never came out with. Can someone please tell me what to do to make it so I can boot from the HD again. I have also reinstalled the latest update for the 4th or 5th time.

Thank You.