WARNING this "LEGACY" version of XCTU does not benefit from the latest features offered by Digi. use should be limited to XBee Serie 1 and 2.
This version contains support for XBee WiFi
Here is the link to download this version LEGACYX-CTU
XCTU Version 5.2.8.6 (compatible Windows XP / 7 / 2000 / 2003 / Vista)
An earlier version 5.1.0.0 is also available, necessary for programming XStream modules (compatible Windows 2000/2003 and XP)
Be careful not to accept the download of all firmware updates at the end of the installation.