Just received my mkr1000 today but can´t upload any sketch to it. I´m using OS X El Capitán and downloaded Arduino IDE 1.6.9 Hourly Build 2016/04/26 06:12
I´ve also resetted de board, installed FTDIUSBSerialDriver_v2_3 driver, installed Arduino SAMD Boards in the boardmanager...
The usb connection is recognized by the system but still doesn´t appear in the Arduino IDE available ports...
If you look at dmesg, you'll see that there are a couple of violations:-
003231.792225 IOUSBHostDevice@fa130000: IOUSBHostDevice::getDescriptorGated: compliance violation: USB 2.0 9.3.5: device returned more than wLength data
003231.793242 Genuine MKR1000@fa130000: IOUSBHostDevice::getDescriptorGated: compliance violation: USB 2.0 9.3.5: device returned more than wLength data
What I did, (and others are saying), is that to get round this, you need to press the reset button on the MKR1000 twice. Like a double click.
Then you should see in dmesg, something like:-
388 set opt:8 -> 0
7615 set opt:8 -> 0
7616 set opt:8 -> 0
7630 set opt:8 -> 0
7632 set opt:8 -> 0
7657 set opt:8 -> 0
7664 set opt:8 -> 0
Now you should see the device in /dev/
mbp:~ nanomoog$ ls -las /dev/tty.usbmodemFA131
0 crw-rw-rw- 1 root wheel 17, 8 18 May 22:53 /dev/tty.usbmodemFA131
Now, (going back to the Arduino IDE), I can see the correct port and talk to it.
So the double tap of the reset button seems to be the fix.