Dave Peterson wrote:

Does the workbook have lots of shapes (pictures, controls)???

Edit goto|special|Objects
hit delete to remove them (all at once).


........................

Gord Dibben wrote:
You have several large transparent autoshapes overlayed in A1.

Can find by F5SpecialObjects

Delete these and file drops to 13.5 kb



Yep, that was it.

My friend had drawn a border around some text and somehow there were
many thousands of copies of it, all in the same place on top of each
other. When I did "select all-delete" it wasn't deleted, it just
became invisible (which makes no sense to me - is that a bug in
Excel?)

PS: Any ideas how somebody could manage to do that (I mean make
several thousand copies of an object)? Two or three copies I could
understand but not thousands...(!)