Can you paste in the exact code you're running/be sure you're using the latest code? The latest example doesn't use a
-m flag and instead relies on
The error message you're seeing is a USB comms error of some kind. @kevin may be able to shed some light on it, but it may resolve itself if the code you're running is in fact old.
The fact that the text is failing to send can be for a couple of reasons. The most likely reason is that the SIM900 (the chip in the center of the GPRS Module) has not yet connected to the cell network. You're connected to the network when the green LED labeled
NETLIGHT is blinking once every three seconds. If it's blinking once a second then the device is still trying to connect. If that's the issue you can increase the 10-second
setTimeout to give the SIM900 more time to connect before trying to send the SMS.
The "type" of number shouldn't matter, so long as it's 10+ digits.