Ah great. Thanks! It works perfectly now.

I have another question:
I am trying to create radio buttons that control whether the double click event is capable of occurring. I've created the radio button code:
Public Sub SetOptionButtonStates()

Dim PAL_Create As Boolean
Dim PO_Create As Boolean
PAL_Create = False
PO_Create = False

End Sub
Sub OptionButton3_Click()


PO_Create = True
PAL_Create = False

End Sub
Sub OptionButton5_Click()

PAL_Create = True
PO_Create = False


End Sub
And I have nested an If statement in the beforedoubleclick event sub:
Public Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
    'Override the default double-click behavior with this function.
    
    Cancel = False
    
   
    

    
    
 
    'Declare variables.
    Dim wks As Worksheet, xRow As Long
    
    'If an error occurs, use inline error handling.
    On Error Resume Next
    
    'Capture double-clicked cell
    Target.Select
    'Capture double-clicked row
    seRow = Target.Row
    

    seCol = 0
    'Insert in Row 15 of Sheet4
    'xRow = Sheet4.Cells(Sheet4.Rows.Count, 1).End(xlUp).Row + 1
    'For first product added to purchase order
    
    If PO_Create = True Then
        If Sheet4.Range("VendorName") = "" Then
        xRow = 15
        Sheet4.Cells(22, 6) = Cells(seRow, seCol + 5)
        Sheet4.Cells(xRow, 3) = Cells(seRow, seCol + 2)
        Sheet4.Cells(xRow, 9) = Cells(seRow, seCol + 6)
        Sheet4.Cells(xRow, 10) = Cells(seRow, seCol + 9)
        Sheet4.Cells(xRow, 1) = Cells(seRow, seCol + 7)
        Sheet4.Cells(xRow, 2) = Cells(seRow, seCol + 8)
        
        MsgBox "New Order Started: Producted Added to PO"
    
    'If trying to add another product to purchase order, check to make sure the vendor is the same
    Else
        If Sheet4.Range("VendorName") = Cells(seRow, seCol + 5) Then
            Dim i As Integer
            
            For i = 16 To Sheet4.Range("Shipping").Row
                If WorksheetFunction.Trim(Sheet4.Cells(i, 1).Value) = "" Then
                    xRow = i
                    Exit For
                End If
            Next i
            
            If i = Sheet4.Range("Shipping").Row Then
                Sheet4.Rows(Sheet4.Range("Shipping").Row - 1).EntireRow.Copy
                Sheet4.Rows(Sheet4.Range("Shipping").Row).Insert Shift:=xlDown
                Application.CutCopyMode = False
            End If
            
            Sheet4.Cells(xRow, 3) = Cells(seRow, seCol + 2)
            Sheet4.Cells(xRow, 9) = Cells(seRow, seCol + 6)
            Sheet4.Cells(xRow, 10) = Cells(seRow, seCol + 9)
            Sheet4.Cells(xRow, 1) = Cells(seRow, seCol + 7)
            Sheet4.Cells(xRow, 2) = Cells(seRow, seCol + 8)
    
            MsgBox "Product Added to PO"
        
        Else
            MsgBox "This item is not from the same vendor"
    End If
    End If
    
    Application.EnableEvents = True
    Application.ScreenUpdating = True
   End If
    End Sub
But now the feature of adding a product by double-clicking doesn't work. I can't figure this out...