There's no way to change the drop down arrow's colour.

You could use programming to change the colour of the heading cell when
a column is filtered. There are sample files he

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

Under Filters, look for 'FL0022 - FilterClick Colour' or 'FL0014 -
Colour Filter Headings'

Loris wrote:
In Excel 2003, The triangle in the drop down list button for any field that
is being used to filter a list is blue. I have a hard time distinguishing
the color. Is there any way to change the color in the triangle?


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