                   WESTERN DIGITAL FAX DOCUMENT #xxxx

DISK COMPRESSION ISSUES AND HARD DISK INSTALLATION
==================================================
 The use of disk compression utilities to increase available hard disk
 space is becoming more common. When PC disk subsystems are upgraded 
 with additional storage (adding a second hard drive), configuration 
 issues may arise that make access to the existing compressed data
 difficult. This document was created to address some of the common 
 disk compression issues encountered when installing a second hard 
 drive.

 The following disk compression products are covered:

    DoubleSpace (included in Microsoft MS-DOS versions 6.0 & 6.20)
    DriveSpace (included in Microsoft MS-DOS version 6.22)
    
 While other less common disk compression utilities exist - and are not 
 discussed in this document - contacting the software manufacturer for 
 technical support is always the best idea. Some phone numbers for the 
 manufacturers of disk compression utilities are located at the end of 
 this document.


ISSUES SPECIFIC TO DOUBLESPACE AND DRIVESPACE
=============================================
 If you are installing a second hard drive in your computer and your
 existing drive is compressed with DoubleSpace or DriveSpace, it is
 easiest to install the new drive as the secondary/slave drive. After
 installing the new drive as the slave, if you are unable to access
 one or more of your compressed drives, run the DBLSPACE.EXE or
 DRVSPACE.EXE program and choose Mount from the Drive menu. This
 lists any unmounted compressed volume files and provides the option
 to mount the compressed volume(s).

 If you wish to make the new drive the primary/master drive and your
 existing drive the secondary/slave drive be sure to follow the
 special instructions for DoubleSpace/DriveSpace users as specified
 in the following sections.

   NOTE: If you encounter problems using DoubleSpace or DriveSpace,
   contact Microsoft MS-DOS support at the number listed at the
   end of this document.


GENERAL INSTALLATION RECOMMENDATIONS
====================================
 The installation instructions below will allow the drive to be used as
 either a bootable master or slave drive. If the ability to boot drive
 D: at some later time is not an issue, use DOS's FDISK and FORMAT or
 Disk Manager to configure drive D: and skip sections I, II and III.

 I. BEFORE YOU START
    a. Make sure you have the following: 
      1. A bootable DOS disk with FDISK.EXE and FORMAT.COM.
      2. Record the Cylinder/Head/Sector information for your existing
         hard drive currently specified in your CMOS setup.
      3. Master/Slave jumper information for your existing hard drive.
      
                                 - 1 -

      4. If you use Microsoft DoubleSpace or DriveSpace disk compression
         on your existing drive AND you are installing the new drive as
         the primary/master drive, carry out steps 1 - 6 in the "Special
         Instructions For Users of DoubleSpace/DriveSpace" section
         (below) before proceeding with section Ib.
    b. Temporarily install the Caviar drive as the only hard drive. 
      1. No jumpers are required to support standalone mode on the 
         Caviar drive.
      2. Make sure the 40 pin IDE cable is disconnected from the
         existing drive.
      3. Boot the system and configure the C: drive parameters through 
         your system configuration utility. For the AC2540 use 1024 cyl, 
         16 heads and 63 sectors.
    c. Start the system from a bootable DOS disk in floppy drive A:.
      1. For a bootable DOS installation, continue at section IIa.
      2. For a bootable DISK MANAGER installation, continue at section
         IIIa.     


 II. USING DOS (528mB BOOTABLE,  NON-Disk Manager installation)
    a. At the A> prompt, type FDISK and press return.
      1. Choose option 1 (default), Create DOS partition... Press enter.
      2. Choose option 1 (default), Create primary DOS partition. 
         Press enter.
      3. Accept the default "Y" use all available space for DOS
         partition and set the partition active.
      4. Press any key to continue.     
      5. Press any key to reboot from the bootable DOS disk.
    b. At the A> prompt, type FORMAT C: /S and press return.
      1. Answer "Y" to Destroy all data on non-removable disk.
      2. The screen should report FORMATTING 504 MB.
    c. When Format is complete, remove the floppy from drive A: and reboot.
      1. Check to make sure the drive boots properly to drive C:.
        a. If the drive boots properly, continue with step d.
        b. If the drive does not boot properly, rerun steps starting at Ic.
    d. Turn off the computer and re-install your existing drive along
       with the new drive.
      1. Set the drive jumpers for primary/master drive (drive C:) and
         secondary/slave drive (drive D:) as appropriate.
    e. Start the system and change the CMOS drive data for drives C: D:.
      1. Configure the C: and D: drive parameters through your system 
         configuration utility. C: drive parameters refer to the
         primary/master drive and D: drive is the secondary/slave.
    f. Reboot the system from the C: drive.
      1. The boot process should complete successfully and bring you
         to the C> prompt.
    g. If you use Microsoft DoubleSpace or DriveSpace disk compression
       on your existing drive AND you installed the new drive as
       the primary/master drive, carry out steps 6 - 9 in the "Special
       Instructions for Users of DoubleSpace/DriveSpace" section (below)
       to re-enable the disk compression.
    h. This completes the installation of your new drive. If you change
       to the new drive and run the CHKDSK command, it should report
       approximately 527,500,000 bytes total disk space.

 
 
                                 - 2 -

 III.  USING DISK MANAGER (540mB BOOTABLE)
    a. At the A> prompt, insert the Disk Manager disk, type DM and
       press enter.
      1. Choose option E, Easy Disk Installation.
      2. When prompted, insert your bootable disk in drive A:.
    b. When installation completes, remove the floppy from drive A:
       and reboot.
      1. Check to make sure the drive boots properly to drive C:.
        a. If the drive boots properly, continue with step c.
        b. If the drive does not boot properly, rerun steps starting at Ic.
    c. Turn off the computer and re-install your existing drive along
       with the new drive.
      1. Set the drive jumpers for primary/master drive (drive C:) and
         secondary/slave drive (drive D:) as appropriate.
    d. Start the system and change the CMOS drive data for drives C: D:.
      1. Configure the C: and D: drive parameters through your system 
         configuration utility. C: drive parameters refer to the
         primary/master drive and D: drive is the secondary/slave.
    e. If you are leaving your existing drive as the primary/master
       drive, reboot the system from the C: drive and carry out steps
       e1 and e2.
      1. Insert the Disk Manager floppy, change to that floppy drive and
         type DMCFIG and press enter. 
      2. Follow instructions and allow DMCFIG to modify CONFIG.SYS. This 
         will copy the proper files onto your existing C: drive to
         support the Disk Manager partition on drive D:.
    f. If you use Microsoft DoubleSpace or DriveSpace disk compression
       on your existing drive AND you installed the new drive as
       the primary/master drive, carry out steps 6 - 9 in the "Special
       Instructions for Users of DoubleSpace/DriveSpace" section (below)
       to re-enable the disk compression.
    g. Reboot the system from the C: drive.        
      1. The boot process should complete successfully. 
      2. If you change to the new drive and run the CHKDSK command, it
         should report approximately 539,750,000 bytes total disk space.

                                 
SPECIAL INSTRUCTIONS FOR USERS OF DOUBLESPACE OR DRIVESPACE
=========================================================== 

IMPORTANT: Follow the instructions in the "General Installation
Recommendations" section above.  You will be referred to this
section if it is appropriate.

  STEPS TO TAKE BEFORE INSTALLING THE NEW DRIVE AS THE MASTER DRIVE
  -----------------------------------------------------------------
  1. Copy the DBLSPACE.EXE (or DRVSPACE.EXE) file to the bootable
     disk you created in Step Ia1.

  2. Use the ATTRIB command to remove the hidden and system
     attributes from the DBLSPACE.BIN and DBLSPACE.INI (or 
     DRVSPACE.BIN and DRVSPACE.INI) files. These files are located
     in the root of drive C: (or the root of the host for drive C:
     if C: is compressed).  For example, if drive C: is compressed
     and H: is the host for C:, type the following commands:




                                 - 3 -

        ATTRIB -H -S H:\DBLSPACE.BIN
        ATTRIB -H -S H:\DBLSPACE.INI
                                 
      Note: DriveSpace users substitute DRVSPACE for DBLSPACE.

  3. Copy these files to the bootable DOS disk you created in
     Step Ia1. For example:

       COPY H:\DBLSPACE.BIN A:\DBL.BIN
       COPY H:\DBLSPACE.INI A:\DBL.INI
 
      Note: DriveSpace users substitute DRVSPACE/DRV for DBLSPACE/DBL.

  4. Use MS-DOS Edit to edit the A:\DBL.INI file and delete the
     ActivateDrive= line(s). For example, if drive C: is compressed
     and hosted on drive H:, delete the line that reads:

       ActivateDrive=H,C0

  5. Save the A:\DBL.INI file and exit from Edit.

  STEPS TO TAKE AFTER INSTALLING THE NEW DRIVE AS THE MASTER DRIVE
  ----------------------------------------------------------------
  6. At the DOS prompt, carry out the following command:

       DIR C:\*.BIN /A

     If you do not see the DBLSPACE.BIN or DRVSPACE.BIN file in the
     root of C, copy the BIN file from the boot disk you created
     before installing the new drive. For example:

       COPY A:\DBL.BIN C:\DBLSPACE.BIN
                -- or --
       COPY A:\DRV.BIN C:\DRVSPACE.BIN

  7. Copy the INI file from the boot disk you created in 1a to the
     root of your C: drive.  For example:

       COPY A:\DBL.INI C:\DBLSPACE.INI
                -- or --
       COPY A:\DRV.INI C:\DRVSPACE.INI

  8. Restart your computer from drive C.

  9. Run the DBLSPACE.EXE/DRVSPACE.EXE program from the DOS boot
     disk and choose Mount from the Drive menu. Select the volume
     file to mount from the list provided.  Repeat this step for
     each unmounted compressed volume file.


DISK MANAGER INSTALLATIONS
==========================
 If after moving the Caviar drive to the D: drive position the blue
 banner for Disk Manager is not displayed or the message "BAD OR MISSING
 XBIOS.OVL" is displayed during boot up, follow these steps to correct
 this error.


                                 - 4 -

 1. Boot the system from a bootable DOS 6.X diskette in drive A:. Check
    that drive C: is fully accessible and all files are present.
 2. Insert the Disk Manager floppy, change to that floppy drive and
    type DMCFIG and press enter. 
 3. Follow instructions and allow DMCFIG to modify CONFIG.SYS. This 
    will copy the proper files onto your existing C: drive to support 
    the Disk Manager partition on drive D:.
 4. Remove the floppy from drive A: and reboot. Proper access to the
    Disk Manager partition on drive D: should now be established.


COMPRESSION UTILITY MANUFACTURERS SUPPORT NUMBERS
=================================================

CubeIt - SoftLogic Solutions, main number (603) 627-9900
                              support number (603) 644-5555
                              BBS number (603) 644-5556

DoubleSpace or DriveSpace - Microsoft, main number (206) 882-8080
                                       MS-DOS support (206) 646-5104
                                       BBS number (206) 936-6735
                                       FastTips service (800) 936-4200

Stacker - STAC Electronics, main number (619) 431-7474
                            BBS number (619) 431-5956          
                            FAXback service (619) 431-8585

SuperStor - AddStor (no longer in business)

     


























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