When you START excel????
Are you opening any specific file (doubleclicking on it in windows explorer) or
are you just starting excel with a blank workbook?
The only way I get this message is when I'm closing a file that has a reference
set to another workbook. And I would think that would be pretty unusual to be
happening when you're opening excel.
But....
Start excel
Get that message and dismiss it.
Open the VBE (alt-f11 is one way)
Hit ctrl-r to view the project explorer.
It'll show you all the workbooks (with their projects) that are open.
Now comes the detective portion.
Select each workbook/project (just like selecting a file in windows explorer)
Then click on Tools|References
Look for a reference to any other open workbook.
Ignore these if they are checked:
Visual Basic For Applications
Microsoft Excel xx.0 Object Library
Microsoft Office xx.0 Object Library
Microsoft forms xx.0 Object Library
If you see any checked that have a one word description, look over to the
project explorer window.
You'll see:
VBAProject(book1.xls)
OtherProject(book2.xls
Look for a match in the project name (before the workbook name in ()'s)
If you uncheck it, you'll will eliminate the reference. But if it's for a
workbook that was developed by your company, you may want to raise a complaint
so you don't break anything.
If it turns out that there's a reference in the new book1 (no extension), then
your Book.xlt workbook template could have that reference--and newly created
workbooks are inheriting this setting.
Open your book.xlt file and remove the reference, then save that template file
in the same location.
Remember, you may want to check out why this is happening before you "fix" the
symptom.