Yes (with slight correction):

Public Function ColorCell(MyCell As Range, Color, Optional Message) As Variant
MyCell.Interior.ColorIndex = Color
If IsEmpty(Message) Then MyCell = "" Else MyCell = Message
End Function
Sub Color_red()
'
' Color_red Macro
' Set cell color to red
'

'
Dim x As Variant
x = ColorCell(Range("a2:a7"), 3, "This should be red")
End Sub

"Ola" wrote:

Is it possible to make this work?

Public Function ColorCell(MyCell As Range, Color, Optional Message) As Variant
MyCell.Interior.ColorIndex = Color
If IsEmpty(Message) Then ColorCell = "" Else ColorCell = Message
End Function

Ola