Martin,
Thanks for your solution. That does work when those two cells are all I
have. However, my dates (monthly) range for several years, from A2:A100.

Again, thanks,
casey

"MartinW" wrote:

Hi Casey,

Try Data Validation,
Say your start date cell is D4 and end date cell is E4
Click in E4, go to DataValidationSettings Tab, select Custom
from the dropdown box and set Formula is: =E4D4
Then click on the Error Alert tab and set the message
you wish to appear.

This will work fine in Excel, however, I know nothing
about whether the functionality will hold when
transferred to a web page.

HTH
Martin


"casey" wrote in message
...
I have an interactive chart with four drop down list boxes. Two of these
are
the Start Date and End Date. It all works fine. However I'm trying to
restrict the user from selecting an End Date that is earlier than the
Start
Date. No luck as of yet. I want to eventually post this on a web page.

thanks,
casey