Darren

Yes, but so's my code.

I thought it was D5 not E5.

Here's the amended code.
Option Explicit

Private Sub Worksheet_SelectionChange(ByVal Target As Range)

    If Target.Address(0, 0) = "E5" Then
        Range("D15").Value = "COMPLETED"
        
        With Range("H43")
            .NumberFormat = "dd.mm.yyyy"
            .Value = Date
        End With

        Range("C16").Formula = "=Delivery!$C$16"
        Sheets(Array("Delivery")).PrintOut Copies:=1
    End If

End Sub
To use this code right click the tab of the worksheet where you want to click E5 and select View Code.

You should now see the worksheet's module.

Paste the code in there and close VBE (ALT+Q) to return to Excel.

Now when you click on E5 the code should run.