Just to let you guys know that I found my problem.
I had several small graphics hidden in a cell that had been minimized there
by someone else. By pressing F5, then "Special", then "Objects", then OK, I
could find my graphics and delete them.
I hope this will help others.

"Anik" wrote:

Hi,
I have an Excel file of 1 worksheet, containing data in about 20 rows by 20
columns, which is 310 kB ! I noticed copying the range of cells A3:E7 and
pasting it doubles the file size, but I cannot find anything wrong in those
cells. I tried the following:
1) If I copy all worksheet and paste it in a new worksheet file, the new
file size is the same, 300kB
2) If I copy and paste all the data column by column, the new file size is
16 kB !
3) If I copy all worksheet and paste values only, the new file size is 14 kB
4) If I delete all the data and the cell formats in the original worksheet,
I still get a large size of 300 kB !
This is weird. I have nothing in the worksheet, no hidden worksheet, and I
really deleted the rows and columns by selecting them and pressing DELETE.
When I press CTRL-END, the cursor stays at cell A1.

Please help me understand this !

Thanks,
Anik