A. I assume you didn't enjoy the experience of reinstalling the OS and all the applications that were on your original system. Your first step toward safeguarding your system from future catastrophe is to add a tape backup device. When you have current backups on hand, you have the tools to fix any observed fault. (Keeping current backup sets is essential.)
However, if your hard disk isn't accessible, you need an NT boot disk—a nonwritable DOS 3.5" disk that contains the DOS utility Fdisk and the Microsoft Windows NT Server 4.0 Resource Kit's Disksave tool. To fix the hard disk's boot partition, run Fdisk /mbr from the DOS 3.5" disk or use Disksave, assuming you performed an earlier backup of the boot partition with Disksave. To avoid boot-partition corruption, install a current antivirus application. Viruses are the most common cause of corrupted boot partitions. Also, remember to keep the antivirus application current.
You should include a copy of the registry on disk. Simply run Rdisk, which you can find in the NT 4.0 directory. To keep your registry backup up-to-date, remember to run Rdisk every time you add a new application, add new users, or alter permissions.
If these methods fail, send the disk to a repair specialist such as DriveSavers Data Recovery. And keep your checkbook handy.