XL2000: Error Message: File Format Is Not Valid

When you open a file in Microsoft Excel, the following error message appears: NOTE: Microsoft Office 2000 has built-in functionality that allows you to get more information about difficult-to-troubleshoot alerts or error messages. If you want to enable this functionality for this and other error messages in Microsoft Office 2000, please download the Microsoft Office 2000 Customizable Alerts file from the Microsoft Office Update Web site at the following address: NOTE: If you reached this article by clicking the Web Info button in an error message, you already have Customizable Alerts enabled.

Multiple Versions of Excel Installed

If you have more than one version of Excel installed on the same computer, refer to the following article in the Microsoft Knowledge Base for steps to solve your problem.

Opening Routed Workbook in Email

If this error appears when you attempt to open a workbook that has been routed to you in e-mail from another Excel user, refer to the following article in the Microsoft Knowledge Base for steps to solve your problem.

Opening a Text File

If this error appears when you attempt to open a text file (.prn, .txt or .csv), refer to the following article in the Microsoft Knowledge Base for steps to solve your problem.