You may want to share the mysterious workbook's name and its project name.

But a workbook can have a reference to another workbook -- each time you open
the "real" workbook, excel will open any workbook that is "referred to" by that
original workbook.

Open your workbook
Go to the VBE
Select your workbook's project
Tools|References

Look at the items that are checked. Do you see that mysterious workbook's
project?

If yes, you can uncheck it.

But ....

The developer may have set that reference on purpose. Maybe he/she wanted to
get data from a worksheet in that workbook--or use any of the functions that
were stored in that workbook.

wrote:

I have a workbook which I save as an addin. Problem is that there is a
mysterious workbook which attaches itself to my primary workbook and it
only displays in the VBA editor. The problem is that this workbook is
not viewable while in Excel. In addition, while in the VBA editor, if
you click on any of the objects of the hidden workbook in the VBA
editor, it as no properties, there are no options to delete or remove.
It doesn't show up on the LINKS MENU in Excel either. Does anyone know
how to remove this phantom workbook?

--

Dave Peterson