Thank u reply. After patched, i solve this problem 

See the code below

Code:

  <input class="easyui-filebox" id="file"  data-options="prompt:'Choose a file...'" />

Code:

  $('#file').filebox('reset');

First, I selected file (Ex : C:\1.txt)
Second, Call "reset" method in filebox object

Then I selected previous selected file (C:\1.txt), the bug happened.
The filebox doesn't display the path/name of the selected file.

I use Internet Explorer 9.
I already patched jquery-easyui-1.4.1-patch