What is the problem?
When trying to connect my Arduino Uno it says "SIO device incompatible"
What did you already try to solve it?
Unplugging and plugging back in, restarting.
Have you tried running in safe mode?
no
Did running in safe mode solve the problem?
did not try, since it is a plugin, and safe mode disables them
Systeminfo Bundle
You can download this in OctoPrint's System Information dialog ... no bundle, no support!)
WRITE HERE
Additional information about your setup
OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible
Running OctoPrint 1.9.1, on windows, printer is a Lulzbot Mini 2, using chrome as browser.