This may help - perhaps the security settings in IE11 are different?
http://msdn.microsoft.com/en-us/library/ie/ms535263(v=vs.85).aspx
Windows Internet Explorer 8 and later. When a file is selected by using the input type=file object, the value of the value property depends on the value of the "Include local directory path when uploading files to a server" security setting for the security zone used to display the Web page containing the input object. For more information, see value.
Windows Internet Explorer 7 and later. By default, Internet Explorer does not include folder or directory path information when uploading files to sites in the Restricted zone. This improves security by preventing information disclosure. Also, to improve accessibility, the input type=file element now contains two accessible elements—one for the input box and one for the Browse button. This change is applicable only to accessibility tools; script implementations are not affected.