If your Windows NT 4.0 or Windows 2000 computer hangs on the empty black screen, immediately after the POST, you could have one or more of the following problems:
1. The MBR (Master Boot Record) is corrupt or infected with a virus.
2. The partition table is damaged.
3. The boot sector is damaged or infected.
4. The NTLDR file is missing or damaged.
If you can start the computer without errors, using a boot floppy, the damage is confined to the MBR, boot sector, or NTLDR. I would backup, and use Disk Administrator to verify the partitions on the boot drive are properly sized. If you have invalid partitions, plan on reformatting the drive and restoring from a previous backup.
Verify that there is no boot virus. You can use an MS-DOS based detector, even if the partition is NTFS.
Run FDISK /MBR from MS-DOS 5.0 or later, or use the Recovery Console FIXMBR and FIXBOOT.
Run a Manual Repair and check the Inspect boot sector and Inspect startup environment.
If the system still won't start, remove the attributes from NTLDR (attrib -r -s -h c:\ntldr) and copy <CD-ROM:>\i386\NTLDR to C:\.
NOTE: If you run a repair, you might want to reapply your latest Service Pack.