Hi EdHansberry,
To better understand the situation, I’d like to confirm the following things:
1.Where is the Excel file stored in, consumer OneDrive, OneDrive for Business library or SharePoint Online team site library?
2.By “try to open in Excel”, do you mean open the file in the synced folder on your computer?
3.Create a test Excel file and store it in the same location, check if it encounters the same issue. It let us know if the issue is related a specific file.
4.Open **Excel>File>Account>**capture a screenshot of Product Information.
5.Which browser do you use? Please change to another browser and check if the issue occurs.
Best regards,
Tim