You can't change the number of items visible in the data validation
dropdown. If you can use programming, there are instructions here for
using a combobox to overlay a cell with data validation:

http://www.contextures.com/xlDataVal11.html

In the combobox, you can change the ListRows property


GoBobbyGo wrote:
Validation property of several cells is set to "list" and "drop-down", where
there are a LOT of options on the drop-down menu.

Is it possible to increase the size of the mini-window that opens when the
drop-down menu is activated, so that more options are shown at the same time?


--
Debra Dalgleish
Contextures
http://www.contextures.com/tiptech.html