The data validation input message appearance is controlled by your
Tooltip settings. To change the font type or colour, or background colour:

(Instructions for Windows XP)
Note: this will also affect ToolTips and Comments

Right-click on the desktop, and choose Properties
On the Appearance tab, click Advanced.
From the Item dropdown, choose Tooltip
Choose a font, font colour, and/or background colour
Click OK, click OK

As an alternative, if you can use programming, you could use a textbox
to display the input message. There's an example he

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

Under Data Validation, look for 'Input Message in Textbox'


ChrisF wrote:
Does anyone know how to modify a data validation pop up box font and
background color?


--
Debra Dalgleish
Excel FAQ, Tips & Book List
http://www.contextures.com/tiptech.html