XL: How to Prevent File Corruption

• Microsoft Excel for Windows, versions 2.x, 3.x, 4.x, 5.0, 5.0c
• Microsoft Excel for Windows 95, version 7.0
• Microsoft Excel for the Macintosh, versions 2.x, 3.0, 4.0, 5.0, 5.0a
• Microsoft Excel 97 for Windows
• Microsoft Excel 98 Macintosh Edition

SUMMARY

The "More Information" section of this article discusses features available in Microsoft Excel that are designed to help prevent data loss. It also discusses ways to prevent file corruption.

MORE INFORMATION

AutoSave

Microsoft Excel versions 3.0 and later include an AutoSave feature. You can customize this feature to automatically save your file after a specific amount of time. It does not make a backup copy of your file, so it does not protect against file corruption; rather, it protects your data in the event that Microsoft Excel unexpectedly quits (for example, if the computer unexpectedly loses power).

For additional information about using AutoSave, please see the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q147778
   TITLE     : XL: How to Enable AutoSave

Automatic Backup

Microsoft Excel versions 2.x and later include an "Always Create Backup" option. This feature will always save the previous version of your Microsoft Excel file when you save changes to your current Microsoft Excel file. This helps to protect against file corruption; however, the information in the backup file will be one save out of date.

This option can be accessed from the Save As dialog box by clicking the Options. By default, this option is not selected. To change this option for all new documents, modify the template for the default startup worksheet or workbook. Refer to your "Microsoft Excel User's Guide" or Help for more information about the Always Create Backup option.

For additional information about customizing the default document template in Microsoft Excel, please see the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q83815
   TITLE     : Excel: Customizing Default Document Templates

Hard Disk Maintenance

A hard (or fixed) disk is a mechanical device with moving parts. Like all mechanical devices it will eventually wear out and fail; hard disk manufacturers often measure the reliability of their drives as the average number of hours before failure or "mean time between failure" (MTBF).

As a hard disk wears out, portions of it become unreadable and are often referred to as bad sectors. One side effect of this is file corruption; if a file is stored on a portion of the hard disk that becomes unreadable, the file can no longer be retrieved.

One method for combating file corruption is to perform maintenance on your hard disk on a regular basis. One recommended schedule involves running ScanDisk or a third-party hard disk utility to check the file structure of the hard disk once a week. Then, run the utility once a month to perform a surface scan of the hard disk media. For more information, consult the manual for the maintenance utility program. Note that if you have Plus! for Windows 95, you can use the System Agent to schedule ScanDisk to run automatically.

For additional information about using hard disk utilities with Windows 95, please see the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q120442
   TITLE     : Using Hard Disk Utilities with Windows 95

• Exit Windows before you restart or shut down the computer.
• Move sources of electromagnetic radiation (such as radios, fax machines, televisions, stereos, speakers, et cetera) away from your computer.
• Do not place floppy disks on top of a computer monitor (it is a source of electromagnetic radiation).
• Regularly scan your computer for viruses.
• Store floppy disks in a disk storage container (such as the box the disks came in) to prevent dust from building up on the disks.
• Prevent dust from building up around your computer.

Backing Up Data

One of the best ways to prevent data loss is to back up data regularly. The more important your data, the more frequently you should back it up.

If you consider your information critical, it is recommended that you save your files to at least two different locations, at least one of which is a removable media such as a floppy disk or a computer tape. The removable media should then be stored in a fireproof safe. Note that there are different grades of fireproof safes; for removable media to survive a fire, the interior temperature of the safe must not exceed 110 degrees Fahrenheit during the fire. Check with the manufacturer of your safe for more information.

For additional information about backing up data with Windows 95, please see the following articles in the Microsoft Knowledge Base:

   ARTICLE-ID: Q133153
   TITLE     : Microsoft Backup for Windows 95 Questions and Answers

   ARTICLE-ID: Q136621
   TITLE     : Description of Full, Incremental, and Differential
               Backups

For additional information about using System Agent to schedule backups, please see the following article in the Microsoft Knowledge Base:

    ARTICLE-ID: Q137749
    TITLE     : How to Perform an Automated Backup with System Agent

REFERENCES

For more information about Creating Automatic Backups, click the Index tab in Microsoft Excel 97 Help, type the following text

   backing up