@alexandros problem solved ! the directory to pd search path was not set. Thanks for the fast answers.
Have a good day

@alexandros comport is installed in my home

@alexandros no its not in path of pure data maybe its this but the strange thing is that without doing it before, it worked normally.

@lacuna

hey thanks for replying the error message is : comport couldn't create but comport is installed

Hello everyone, I have a problem with comport object.
i'm trying to connect my arduino to pure data via serial to control my patch with potentiometers.
a few days ago everything was working perfectly then one day when i turned my computer back on the comport object was dash out.
i tried everything, uninstalled pure data, uninstalled comport from find externals but nothing worked. If anyone has an idea, it would help me a lot. Btw I'm on archlinux.