Error opening serial port /dev/ttyACM0

[donbowman]

I'm on Ubuntu 16.10 [kde].
I have a QIDI Tech I.
W/ the makerbot sw, i can use the serial port.
W/ the Simplify3D sw I cannot use the serial port.

I am in the 'dialout' group (which /dev/ttyACM0 is 660 root:dialout).
I have also tried with 'sudo'
I have also tried chmod 666 /dev/ttyACM0

The error given when i try to 'connect' from the machine panel is:

Code: Select all

Attempting connection at /dev/ttyACM0...
  Permissions error connecting to port
    Is there another application already connected to this port?
    Please make sure to add your username to the 'dialout' group by typing 'sudo usermod -aG dialout <myusername>'
  Error opening selected port.

I'm not sure where to go. I tried to strace the process but I get EPERM on a clone() for some reason.

Suggestions?

[brian442]

The error message already says what the problem is. Something else is connected to the port already. Read this:
https://www.simplify3d.com/support/faq/#faq-4630

You probably forgot to disable the makerbot background services

[srlake314]

What if you dont HAVE Makerbot then? What else could it be?