Validating cells based on content and background color

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Sub test()
Dim rng As Range
Dim lRow As Long
lRow = Sheets("Sheet1").UsedRange.Row
Set rng = Sheets("Sheet1").Range("A" & lRow & ":DD" & lRow)

With rng
    For Each cell In rng
        If cell.Interior.ColorIndex = 6 Then
            If cell.Value = Empty Then
                MsgBox "Please ensure that you have filled      " & Chr(10) & "out all empty yellow fields'.", vbOKOnly + vbInformation, "Please fill empty fields"
                Exit Sub
            End If
        End If
    Next cell
End With
End Sub