Issues installing Arduino Uno with Mac El Capitan OS 10.11

I just installed the mac 10.11 (El Capitan) OS on my older MacBook Pro last night and was disappointed to find the arduino IDE shuts down and gives the attached errors when I attempt to launch the application. The Arduino starter kit owners manual states (p.17) that the IDE download is compatible with “OS 10.5 or later.”

I have searched several posts by others in this forum and outside but nothing I have tried so far has helped. A bit frustrating since my current hardware will only support up to OS 10.11 and I took arduino at it’s word with the OS versions supported.

Any feedback is appreciated.


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I believe you have encountered this bug:

That bug has already been fixed but there has not been a new release of the Arduino IDE since that time.

My recommended workaround for this bug is to use Arduino IDE 1.8.7 instead of Arduino IDE 1.8.8. You can download 1.8.7 here: