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From: Anthony Appleyard <XPUM04@prime-a.central-services.umist.ac.uk>
To: KRVW <@NSFnet-Relay.AC.UK:KRVW@sei.cmu.edu>
Date:         Fri, 01 Jun 90 16:09:48 BST 
Message-Id:   <$TGTWCZCFFBTV at UMPA>
Subject:      Virus-L vol 0 issue #0530



Virus-L Digest Mon, 30 May 88, Volume 0 : Issue #0530

Today's Topics

Re: write-protect tabs
RE:  Hard disk disable

------------------------------

Date:         Mon, 30 May 88 17:55:00 LCL
Reply-To:     Virus Discussion List <VIRUS-L@LEHIIBM1>
Sender:       Virus Discussion List <VIRUS-L@LEHIIBM1>
From:         Michael Wagner +49 228 8199645 <WAGNER@DBNGMD21>
Subject:      Re: write-protect tabs

  Terry Sanderson <SANDERS@UTORONTO> writes:
> IBM PC Floppy disks CANNOT be written to when there is a
> WRITE-PROTECT tab on the disk.
>
> I DO have access to technical docs, schematics, etc.  The hardware
> provides a signal to the operating system that there is ... a
> write-protect tab on the disk, but it cannot ... override the
> protection.

  Terry:  Perhaps an overview description of the form of protection,
  where it is provided (in the drive itself, or in the interface
  hardware) and whether this protection can also be expected to be
  in clones would help clarify the situation.

Michael

--------------------

Date:         Mon, 30 May 88 12:01:00 EST
Reply-To:     Virus Discussion List <VIRUS-L@LEHIIBM1>
Sender:       Virus Discussion List <VIRUS-L@LEHIIBM1>
From:         GILL@QUCDNAST
Subject:      RE:  Hard disk disable

David Slonosky asked about a disable for a hard disk

     In answer to your submission to VIRUS-L (at least part 1), there is a
program on the MSDOS disk called BOOTF.  If I understand it correctly (i.e.
read the manual), it will software disable the harddisk so that any program
running from floppies doesn't see the harddisk.  This was written because some
old commercial programs used a copy-protection scheme that crashed their
program when run on a machine with a harddisk.  Really dumb, eh!!

     However, since this is a software disable, I suppose it can be
circumvented by a virus checking for this kind of thing.  Those more
knowledgable could perhaps comment on that.

                                           ____________________________________
Arnold Gill                               | If you don't complain to those who |
Queen's University at Kingston            | implemented the problem, you have  |
gill @ qucdnast.bitnet                    | no right to complain at all !      |
                                           ------------------------------------