home *** CD-ROM | disk | FTP | other *** search
- Path: sparky!uunet!decwrl!access.usask.ca!ccu.umanitoba.ca!ciit85.ciit.nrc.ca!brandonu.ca!dueck
- Newsgroups: comp.os.msdos.programmer
- Subject: Re: Invalid Media: Correction??
- Message-ID: <1992Aug31.155902.2191@brandonu.ca>
- From: dueck@brandonu.ca
- Date: 31 Aug 92 15:59:02 CST
- References: <1992Aug27.141456.24146@schunix.uucp>
- Organization: Brandon University, Brandon, Manitoba, Canada
- Lines: 47
-
- In article <1992Aug27.141456.24146@schunix.uucp>, sonix@schunix.uucp (Duane Morin) writes:
- > Ok, so, I stay home for ONE sick day, and when I come back, the boss tells me
- > that his computer is dead. This is what it says: Missing Operating System.
- >
- > <deleted>
- >
- > My question: We don't want to completely reformat this disk, there's alot
- > of information on it that we hope not to lose. I would figure that the
- > boot sector has been trashed, not the file allocation tables, so maybe
- > we can resurrect some of the data. Does anyone know the best way to tackle
- > this fairly nasty problem? Like, can I get to the hard disk to write a new
- > media descriptor? How would I go about doing that?
- >
- If you have another computer with the same hard disk, use debug to
- transfer a copy of the boot sector from the good disk to the bad disk.
-
- On the machine with the good disk:
- C:> debug
- -l 100 2 0 1
- -n bootblok
- -r cx
- -CX 0000
- : 0200
- -w
- Writing 00200 bytes
- -q
- c:>
-
- What you have done is to read (l=load) into cs:100 from drive c (2)
- starting at block 0 for 1 block.
- The n command specifies a name for the w(write) and r(read) commands.
- The r cx command displays the contents of the CX register, which
- you then modify to 0200 (512) bytes.
- The w command writes CX bytes to the named file.
-
- On the machine with the bad disk, read the bootblock file into
- memory and write it to disk
-
- A:> debug bootblok
- -w 100 2 0 1
- -q
- A:>
-
- Let me know how it works out.
-
- Gery Dueck
- dueck@brandonu.ca
-