Only by not allowing the workbook to be saved or closed before the cell is
filled in.
This would also require that users enable macros which opens a second can of
worms.
i.e. What do you do if users do not enable macros.
Anything else relies strictly on educating your users.
You could just place a message formula in the cell like
=if(and(A1<>"",B1=""),"Please enter a value in B1","")
See this google search thread for some code if you wish to go that way.
http://snipurl.com/16bvu
I included several posts from Dave Peterson so browse through them.
Gord Dibben MS Excel MVP
On Mon, 1 Jan 2007 18:47:15 -0800, Vinesh Rao <Vinesh