I´m working on my project but few days ago i started get this error. I´m using arduino with ethernet shield.
From computer, using the same connection, I´m able create telnet connection on arduino.mydevices.com:8442
 MAC: FE-D0-E0-D0-DB-D1
 Getting IP…
 My IP: 192.168.0.26
 Connecting to arduino.mydevices.com:8442
 Ready (ping: 428ms).
 Heartbeat timeout