A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Do you do VBA programming? I would look in the visual basic editor and then go to tools and then references. You should have references to VBA, Excel, Office and OLE Automation. Application should be a member of Excel. When an object is being resolved, it starts at the top of the list so if you have a reference to something with an application member that is higher than Excel in the list this might be the problem. (you can try unchecking that reference)
References are set at the workbook level. So possibly your default template for a workbook has an errant reference in it. First try creating a new workbook but use a specific template rather than the default workbook template. If that workbook doesn't have the problem, then I would say that confirms that your default template has become "corrupted" in some way (maybe not truly corrupted but at least from a references standpoint).
You would then need to create a new default workbook template.
The problem could also be caused by a new addin you have added. You can try starting Excel in safe mode (addins won't be loaded) and see if when you create a new workbook it doesn't have the problem. Still it seems to me that if an addin is the problem it would affect existing workbooks.
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Regards,
Tom Ogilvy