UploadFile Control Not Allowing Multiple File Selection in IE 11

ASP.NET Framework 4.5.1.  IIS 7.
I upgraded my framework from 3.5 to 4.5.1 to allow use of the AllowMultiple property in the FileUpload control.  It works when I view the site in Firefox.  But it only allows one file selection in IE 11.  Anything I can do to make this work?
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