Problem connecting 2 arduino DUEs through native ports to PC

Hi, I am using 2 arduino DUEs and arduino 1.5.8 IED on windows 10, with the keyboard library. Programming port works fine but almost every time I plug in the DUEs with the native ports the first DUE works fine and can send keystrokes to the computer but when I plug in the second DUE native USB I get a message that the USB is not recognized.

Pressing the reset button on the second card usually do not retrigger this message but now its native USB appear as a bossa program port, not an arduino DUE, in the device manager and the sketch can’t sent keystrokes to the PC!

This is how it usually works but there are many other combinations. Sometimes even the first DUE to be connected through the native port malfunctions in a similar way. On rare occasions, just after I have uploaded code to them and then reconnected them to the native port, both cards might actually show up in the device manager as an arduino DUE. Then it is possible to send keystrokes from both of them using the keyboard library. This is however very rare. :frowning:

How shall I proceed to be able to have 2 DUEs simultaneously connected to the PC through the native USB ports?

Appreciate any help. :slight_smile: