----------------------------------------------------------------- STACKER NOTE STACKER NOTE SDEFRAG ERRORS 109/110, 120, AND 170 & STACKER 4.0 (Applies to Stacker 4.0) STAC FAX 4407 (03-28-1994) ----------------------------------------------------------------- BACKGROUND When SDEFRAG detects a media error on your disk, it displays an error message and provides brief instructions on how to correct the media error. This document provides in-depth procedures for correcting the following SDEFRAG errors: Error Description 109/110 170: SDEFRAG is unable to read, write, or verify a physical cluster on the hard disk. This is usually caused by a media error. 120: SDEFRAG is unable to decompress a physical cluster. This is either caused by a media error or corrupted cluster written to the Stacker drive. This document is organized into two procedures. Procedure I remedies SDEFRAG errors that warrant a surface scan utility. Complete this procedure first. If the SDEFRAG error persists, then complete Procedure II. Some steps will differ, depending on whether you are using DOS versions that support preloading such as MS-DOS 6.x, Novell DOS 7, and most releases of PC-DOS 6.x, or if you are using other DOS versions. PROCEDURE I: USING SURFACE SCAN UTILITIES WITH STACKER If a physical hard drive flaw (bad sector) affects the operation of your Stacker drive, then a disk repair utility can be used to detect the damaged areas and correct them. This procedure explains how to use a disk repair utility to repair hard drive flaws in conjunction with Stacker. Norton Utilities' Calibrate, PC Tools' DiskFix, and SpinRite are examples of disk surface scan utilities. SOLUTION To correct physical disk flaws that affect Stacker: - Ensure that a file attribute utility is available - Boot without loading device drivers - Unhide the STACVOL file - Correct the damaged, unreadable areas of your hard drive - Correct coincidental damage to the Stacker drive. First, locate file attribute utilities From the DOS prompt type STACKER . Locate the line that displays drive C. It will look something like this: Drive C was drive C at boot time [ E:\STACVOL.DSK = 173.5MB] The drive letter in brackets (in this case drive E) is your uncompressed boot drive. Go to the DOS directory on that drive and ensure that the DOS command ATTRIB is there. If not, copy it from the DOS directory on the C drive. Clean boot your system Clean boot your system using a bootable floppy diskette. "Clean boot" means to start your computer without loading any device drivers into memory, including Stacker. Refer to your DOS user's guide if you do not have a bootable floppy diskette. Note: if you use MS-DOS 6, see page 178 of the MS-DOS 6 User's Guide for instructions on making a Startup disk. After clean booting, your computer will display an A prompt. Change to the C drive and go to the DOS directory. Type: attrib -s -h -r drive:\STACVOL.* where drive is the letter of the drive you are repairing. This command unhides all STACVOL files on the specified drive. Run the surface scan on the physical hard drive 1. Follow the disk repair utility's instructions for running from a floppy disk. Use the most rigorous pattern testing available (typically 80-pattern) to scan the physical drive containing the STACVOL file, and allow it to repair defective areas on the disk. A rigorous surface scan may take several hours, depending on the size and speed of your hard drive. Note: If you are using Norton CALIBRAT.EXE to perform pattern testing, it defaults to low-level formatting. IDE drives cannot be low-level formatted, so you must override low-level formatting with the following command: calibrat /noformat 2. Remove all disks from the floppy drives and restart the computer. Correct coincidental damage to the Stacker drive 1. Switch to the compressed drive, change to the \STACKER directory, and type: check /f 2. When CHECK prompts you to perform a disk surface test, respond "yes." 3. If CHECK detects errors and prompts you to delete damaged files, respond "yes," then complete the on-screen instructions that CHECK displays. You are ready to run SDEFRAG again. If the SDEFRAG error persists, then complete Procedure II. PROCEDURE II: ENABLE DIAGNOSTIC MODE If the SDEFRAG error persists after completing Procedure I, then CHECK /F must be invoked in a special diagnostic mode to detect and correct corrupted clusters written to the Stacker drive. SOLUTION To detect and correct corrupted clusters on the Stacker drive - Modify your system configuration to enable diagnostic checking - Run CHECK /F with the surface scan option - Run SDEFRAG /R - Restore your system configuration Modify your system configuration Select the appropriate procedure to enable diagnostic checking and start your computer without loading any device drivers into memory: For Preloading versions of DOS 1. Type: ED /I . Upon entering the editor, your cursor will be positioned at the beginning of the first line. From this position, type: /R=0 2. Press Ctrl-Z to save the file. 3. Reboot your computer. When MS-DOS displays the following text: Starting MS-DOS... press and release the F5 key, or press and hold down the SHIFT key. For other DOS versions 1. Type: ED /I . Upon entering the editor, your cursor will be positioned at the beginning of the first line. From this position, type: /R=0 2. Press Ctrl-Z to save the file. 3. Type ED /C to modify the CONFIG.SYS file on the C drive. Remark all device drivers and programs other than STACKER.COM and SWAP.COM. The following example illustrates a typical CONFIG.SYS file with REM's in place: buffers=20 files=30 lastdrive=e REM device=c:\dos\himem.sys REM device=c:\dos\emm386.exe noems REM dos=high,umb REM devicehigh=c:\mouse\mouse.sys /c1 REM devicehigh=c:\dos\smartdrv.sys 1024 devicehigh=c:\stacker\stacker.com device=c:\stacker\sswap.com 3. After you have made the appropriate modifications to your CONFIG.SYS file, save it then restart your computer. Run CHECK /F with the surface scan option 1. Switch to the compressed drive, change to the \STACKER directory, and type: check /f 2. When check prompts you to perform a disk surface test, respond "yes." 3. If CHECK detects errors and prompts you to delete damaged files, respond "yes." Complete the on-screen instructions that CHECK displays, and continue with step 4. 4. From the \STACKER directory, type: sdefrag /r If the SDEFRAG error persists, then complete step 5. Otherwise your system is fully optimized and you can restore its original configuration (see next section, "Restore your system configuration.") 5. If the SDEFRAG error persists, then switch to your computer's slower CPU speed (i.e., press the TURBO button) and run SDEFRAG again. 6. If your computer does not have a secondary CPU speed, or if the SDEFRAG error persists after running SDEFRAG at the slower CPU speed, then do the following: a. Type ED /I . Upon entering the editor, your cursor will be positioned at the beginning of the first line. From this position, type: /C=32 /F=512 b. Press Ctrl-Z to save the file. c. Reboot your computer. If you are using MS-DOS 6.x when it displays the following text: Starting MS-DOS... press and release the F5 key, or press and hold down the SHIFT key. 7. After making these modifications, change to the \STACKER directory on your compressed drive and type: sdefrag /r Restore your system configuration After successfully optimizing your system, return it to its original configuration. Repeat the editing procedure to remove any added switches (/R=0, /C=32, /F=512) from the STACKER.INI file. If you modified your CONFIG.SYS file, remove all the remark statements from the beginning of the device lines. Save the files and restart your system. ----------------------------------------------------------------- Copyright 1994 Stac Electronics