title: Microsoft.Win32.SaveFileDialog valid file name issue
body: <p>Running an application with .NET 4.5, written in C#. When I call a SaveFileDialog I get mixed results on the validation of file names. If I input some of the usual suspects {}&lt;>/| etc. I get an error that the file name is not valid. That's what I would expect.</p>
  
  <p>However, two of the usual suspects in particular cause an issue. If I enter a question mark (?) or an asterisk (*) then when I hit Save nothing happens. No error message is issued about the invalid characters, and the dialog just stays open. I'd like the user to know why nothing happened and tell them the characters are invalid. I can't find anything online about this being a known bug.</p>
  
  <p>Any ideas? I know I can add my own event to FileOK but it only gets executed AFTER the build in one, so that does me no good because the FileOK event never fires.</p>