Hi Bill,

It sounds like the issue you're experiencing is related to the file format of the Excel file. The error message you're seeing suggests that the file may have been saved as a web page instead of a standard Excel file.

To resolve this issue, you can try the following steps:

1. Open a new Excel workbook.
2. Click on the "File" tab and select "Open".
3. Navigate to the location where you saved the problematic Excel file.
4. In the "Open" dialog box, change the file type to "All Files".
5. Select the problematic Excel file and click "Open".
6. If the file opens successfully, click on the "File" tab and select "Save As".
7. In the "Save As" dialog box, select "Excel Workbook" as the file type.
8. Choose a location to save the file and click "Save".

This should save the file in a standard Excel format, which should allow you to open it without any issues. If you're still having trouble opening the file, it's possible that the file may be corrupted or damaged. In that case, you may need to try to recover the file using Excel's built-in recovery tools or seek assistance from a technical support professional.

Let me know if you have any other questions or concerns.