In order to rename a file, you must habe "Rename" permissions.  If so, proceed as follows: 

• In the Filelist panel, select the file that you wish to rename by left clicking on the file name (right-click on Microsoft Internet Explorer).  A pop-up menu appears. 

    

• Select Rename from the menu.

The Rename file dialog box will then appear, as shown below:

    

The current folder name will then be editable.

• Type in the new file name in the Rename to field.
• Click on Update to save changes.