Offizieller Kommentar
Hello those who have problems in installing firmware:
This issue can be solved by downloading and installing Java to Mac OS X 10.10 and Windows 10, where Java has not been installed while earlier versions of Mac and Windows had it.
Please see the manual of DDJ-RX, which explains about this issue in the first section "Read Before Use".
http://pdj-ecom.trafficmanager.net/en/support/software/ddj-rx/#firmware-update
Also, if you use Windows10, the Java download page will ask you the following.
"In Windows 10, the Edge browser does not support plug-ins and therefore will not run Java. Switch to a different browser"
However, you do not have to switch to a different browser and just click the [Agree and Start Free Download] button to download and install the Java.
Then, you will be able to update the firmware on Windows 10.
If you still have any issues, please let us know.
CRM, Pioneer DJ