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	STACKER NOTE                                       STACKER NOTE
	Title: REPLACING BAD OR MISSING SYSTEM FILES
	       (Applies to Stacker for Windows & DOS 3.1 and DOS 6)
	STAC FAX 31701  (6/93)
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	BACKGROUND

	  All bootable drives must contain the hidden DOS system files 
	  (usually IO.SYS and MSDOS.SYS or IBMBIO.COM and IBMDOS.COM). 
	  With the advent of DOS 6, DoubleSpace, and Stacker 3.1, a 
	  third system file is required to gain access to the data if 
	  the user chooses to use compression.  If the user chooses 
	  Stacker compression, this file is the Stacker-aware 
	  DBLSPACE.BIN.  If any of the system files have been damaged, 
	  your system may not start or you may receive a "Non-System 
	  disk or disk error" message.

	SOLUTION

	If you receive a "Non-System disk or disk error" message 
  
	  To restore the DOS system files and still have access to your 
	  compressed data do the following:

	    1.  Insert the Stacker Startup Disk that you created after 
		you ran Stacker Setup, in drive A. 
	
	    2.  If you do not have a Stacker Startup disk, you can 
		create one from your DOS 6 upgrade disks.

		a.  Insert the first DOS Upgrade disk into drive A or B 
		    and switch to that drive.  Type:

			SETUP /F <Enter>
	
		    This process creates a separate, bootable MS-DOS 6 
		    system disk with essential utilities on it 

		b.  To make the new system disk "Stacker-aware," follow 
		    the instructions on page 18 of the Stacker 3.1 
		    Supplement Manual.

	    3.  Restart your system.

	    4.  From the prompt, type:

		    drive:\path\STACKER <Enter>
	
		where drive is the drive letter where your Stacker 
		program files are located and path is the directory 
		containing the files.
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	Copyright 1993, Stac Electronics                    Page 1 of 3












	    5.  Note the drive letter in the square brackets to the 
		right of the boot-time information for Stacker drive C. 
		This letter is the uncompressed drive for Stacker drive 
		C. (If drive C is not compressed, the appropriate drive 
		letter is C.)

	    6.  From the prompt, type:

		    SYS drive: <Enter>
	
		where "drive" is the letter of the uncompressed drive 
		for Stacker drive C.

	    7.  Remove your Stacker Startup Disk from drive A and 
		restart your computer.

	If your system won't start or Stacker won't load

	  You probably have a bad or missing Stacker-aware DBLSPACE.BIN 
	  file.  To repair the file, first follow Steps 1 through 7 in 
	  the procedure listed above.  If you still can't access the 
	  data on your Stacker drive:

	    1.  Insert Stacker Disk 1 into drive A or B.

	    2.  Change to the floppy disk drive by typing:
	
		    A: or B: <Enter>
    
	    3.  From the prompt, type:
	
		    \TOOLS\REDBL drive: <Enter>
	
		where "drive" is the letter of the uncompressed drive 
		for Stacker drive C (this was determined in Step 4 of 
		the preceding procedure).

	    4.  Remove the floppy disk from its drive and restart your 
		computer.

	If you didn't create a Stacker Startup Disk when you ran 
	Stacker Setup

	  First you have to create an MS-DOS 6 Startup Disk:

	    1.  Insert your MS-DOS 6 Setup Disk 1 into drive A or B

	    2.  Change to the floppy disk drive by typing:
	
		    A: or B: <Enter>

    
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	    3.  From the prompt, type:
	
		    SETUP /F <Enter>

	    4.  Follow the instructions on your screen.

	  After you have created your MS-DOS 6 Startup Disk, follow the 
	  procedures in the previous section, "If your system won't 
	  start or Stacker won't load."

	Your system still won't boot

	  If you followed the procedures detailed above and your system 
	  still won't boot, you may have a hardware error, such as a 
	  failing hard drive controller; a failing hard drive 
	  controller cable; a failing sector on the hard drive, or a 
	  failing system board.  Contact your system's manufacturer for 
	  more information.
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	Copyright 1993, Stac Electronics                    Page 3 of 3