try this macro - change the range to suit your range. NOTE: this
will not work if the cells that are green are green because of
conditional formatting!!!! this will only work if they have been
manually colored. if you have conditional formatting involved, you
will need something different.

'--------------------------------------------------------------------------
Sub change_color()

Dim myWS As Worksheet
Dim c As Range
Dim myRange As Range

Set myWS = ActiveSheet
Set myRange = ws.Range("a1:g500") '<--CHANGE RANGE

For Each c In myRange
If c.Interior.ColorIndex = 35 Then 'green
c.Interior.ColorIndex = 34 'blue
End If
Next c

End Sub
'------------------------------------------------------------------------

hope that helps!
:)
susan



On Nov 14, 1:54*pm, (Claudia d'Amato) wrote:
Assume I have a worksheet where some (but not all !!) cells have a background color of light green.

How can I change at once (!) the background color of all those cells to light blue?

All other cells should remain unchanged.

Claudia