Excel file security

Excel workbooks can contain sensitive data that must be protected when residing on a client computer. The underlying security offered by the PI System is not applicable after retrieving the information into a worksheet. Therefore, AVEVA recommends that you secure each workbook file. You can:

• Secure your Excel workbook files with passwords. Passwords will allow only authorized users to view or modify any data in the workbook. For more information, see the Microsoft Office article Protect a workbook.

• Use the most secure practices for setting workbook passwords:

  • Set a password to open the workbook and a password to modify the workbook.

  • Use a mix of uppercase and lowercase letters, numbers, and symbols in your passwords.

  • Select the Encrypt document properties check box to prevent unauthorized users from viewing summary and custom file properties of the workbook.

• Enable Information Rights Management (IRM) on your Excel workbooks. IRM lets individuals and administrators specify workbook access permissions, which can help to prevent unauthorized people from printing, forwarding, or copying sensitive PI System data. After you restrict the permission for a file with IRM, the access and usage restrictions are enforced regardless of where the information is because the access permission is stored in the file itself. For more information, see the Microsoft Office article Restrict access to workbooks with Information Rights Management in Excel. If required, you can set an expiration date for the data in the Excel file. In the Microsoft Office article, see the procedure "Set an expiration date for a file."

• Use Internet Protocol Security (IPSec) encryption on the link between computers that host PI DataLink and file stores that contain Excel workbooks if storing Excel workbooks on remote drives. For more information, see the Microsoft TechNet article What Is IPSec.

• Apply secure file permissions on your Excel workbooks to ensure that unauthorized users do not have access to the contents of the files. For more information, see the Microsoft TechNet article File and Folder Permissions.

• Apply a digital signature to the Excel workbook file. For more information, see the Microsoft Support article Description of digital signatures and code signing in workbooks in Excel.