multiboot 98 nt4 2000

On one computer, I have just installed windows 98SE on FAT32, then installed NT4 workstation and NT4 server on 2 separate NTFS partitions. When I got to the Windows 2000 part-way installing I got 0x0000007B inaccessible boot device error. I remember I could do it before and now I just can’t repeat it. I had windows 98SE, NT4WS, NT4SRV, xppro, 2000pro all on one hard disk on the same computer before. I got into trouble when I started restructure the hard disk. I wonder if somebody can shed some light on this.