Option Explicit
Private oVars As Variables

Private Sub ComboBox1_NotInList(NewData As String, Response As Integer)
On Error GoTo Error_ComboBox1_NotInList

    Dim strMsg As String
    Dim ctl As Control
    ' Return Control object that points to combo box.
    Set ctl = Me.ComboBox1
    ' Prompt user to verify they wish to add new value.
    strMsg = "'" & NewData & "' is not in the list. "
    strMsg = strMsg & "Would you like to add it?"
   
    If strMsg = vbOK Then
        ' Set Response argument to indicate that data
        ' is being added.
        Response = acDataErrAdded
        ' Add string in NewData argument to row source.
        ctl.RowSource = ctl.RowSource & ";" & NewData
        Else
        ' If user chooses Cancel, suppress error message
        ' and undo changes.
        Response = acDataErrContinue
        ctl.Undo
    End If

Error_ComboBox1_NotInList:
MsgBox Err.Number & " " & Err.Description
Resume Exit_ComboBox1_NotInList
End Sub

Private Sub Userform_Initialize()
'Late binding.  No reference to Excel Object required.
Dim xlApp As Object
Dim xlWB As Object
Dim xlWS As Object
Dim cRows As Long
Dim i As Long
  Set xlApp = CreateObject("Excel.Application")
  'Open the spreadsheet to get data
  Set xlWB = xlApp.Workbooks.Open("C:\VBA\ReportData.xlsx")
  Set xlWS = xlWB.Worksheets(1)
  'Range is defined in ReportData
  cRows = xlWS.Range("PlaintiffRange").Rows.Count
  'Populate the list in the combobox.
  With Me.ComboBox1
    For i = 2 To cRows
       'Use .AddItem property to add a new row for each record and populate column 0
      .AddItem xlWS.Range("PlaintiffRange").Cells(i, 1)
      'Use .List method to populate the remaining columns
      .List(.ListCount - 1, 1) = xlWS.Range("PlaintiffRange").Cells(i, 2)
    Next i
  End With

  'Clean up
  Set xlWS = Nothing
  Set xlWB = Nothing
  xlApp.Quit
  Set xlApp = Nothing
lbl_Exit:
  Exit Sub
End Sub

Private Sub cmdOK_Click()
'Define the variable oVars
Set oVars = ActiveDocument.Variables
'Hide the userform
Me.Hide
'Assign the value of the combobox to the variable
oVars("Plaintiff").Value = Me.ComboBox1.Value
'Update the fields in the body of the document
ActiveDocument.Fields.Update
'Clear the variable
Set oVars = Nothing
'Unload the form
Unload Me
End Sub
Private Sub cmdCancel_Click()
'User has cancelled so unload the form
Unload Me
End Sub