NT4 inaccessable boot device

Ive got a Compaq Professional Workstation AP200 with a 10GB IDE hard drive, running NT4 WS SP4, which im having some problems with.

With the drive in the compaq machine i get an “inaccessable boot device” error. Ive tried to boot using last known good config, but it does the same.

When installed as a second drive in a Win2k machine, the second partition of the hard drive works fine but the first partition gives the following error “The file or directory is corrupt and unreadable”. Which i gather from knowledge base means the master boot record is corrupted or missing.

How can i get round this to at least boot the hard drive? How do i rebuild the MBR table??