Hi Don,

Thanks for weighing in on my problem.

You need to understand that the rules were not written specifically to
please one user.

I acknowledge that. But I'm innocent :-) I was just trying to get
this functionality working.

A UDF can only go in a regular module which you may rename, if desired.
A worksheet event macro can only go into the SHEET module of the desired
sheet. Or, it might be able to be put into the ThisWorkbook module if for
many sheets.

When I read this, I didn't understand where the "SHEET module of the
desired sheet" was. It was only when I followed the directions from
the final response that I understood what you meant.

Even following those directions gave me a problem because I didn't
immediately know where the "sheet tab" was (because I use Excel so
infrequently and so sparingly.) But when I finally opened Sheet1's
context menu and then saw Sheet1 highlighted in under Microsoft Excel
Objects in VBA, all the "lights" went on!

And the Worksheet_Change module worked. Hallelujah!!

Again, thanks for your help.

Best wishes,
Richard