Paul, just wondering if you have any idea what is going on?
(Arduino 1.0.5, Teensyduino, Teensy3)
Here is the trend.
Teensy3 is not visible in serial port.
I click upload, it asks me to reset the board.
I reset, Teensy3 is now (magically) visible in serial port.
I proceed to upload, receive error 'download error' from teensy loader
Teensy3 vanishes from serial port
Uploading/rebooting all prompt 'download error' (see image)
Just trying to upload the blink code as a test.
This Teensy3 was working perfectly a few hours ago and I am measuring 5V across it.

(Arduino 1.0.5, Teensyduino, Teensy3)
Here is the trend.
Teensy3 is not visible in serial port.
I click upload, it asks me to reset the board.
I reset, Teensy3 is now (magically) visible in serial port.
I proceed to upload, receive error 'download error' from teensy loader
Teensy3 vanishes from serial port
Uploading/rebooting all prompt 'download error' (see image)
Just trying to upload the blink code as a test.
This Teensy3 was working perfectly a few hours ago and I am measuring 5V across it.
