Just add On Error Resume Next to ignore any errors.
Code:
On Error Resume Next
'clear the Err object
Err.Clear
WordApp.Selection.MoveDown Unit:=wdLine, Count:=1 
WordApp.Selection.MoveRight Unit:=wdCell 
If Err Then
    'Houston we have a problem
    Exit Sub 'or function
End If
WordApp.Selection.TypeText Text:=txtEndUser
Good luck!