Unable to open the requested feature: Error Code -100

I was using training some models using the "reinforcement learning episode manager",

and after some computationally expensive operations,

I am getting

"Unable to open the requested feature"

Check your internet connection and proxy settings in MATLAB web preferendces and then try starting the feature again.

Detailed Information:

Error code: -100

Error message: ERR_CONNECTION_CLOSED

First of all, my internet connection itself is fine, which means that I can use internet without any problem.

FYI, my OS is linux.

My MATLAB web preference is set as the following:

Could I please get some help here.

[Nikhil Sapre]

Hi Joon,

I have couple of questions for you.

• Are you using uifigure?
• Can you try changing your default browser to Chrome and see if the problem goes away?

[Joon-young Gwak]

Thank you for your reply Nikhil,

• Are you using uifigure?

Despite that I did not explicitly create a uifigure, I believe the "Reinforcement Learning Episode Manager" is an

uifigure based App. Instead of error in the original post, I should be getting:

• Can you try changing your default browser to Chrome and see if the problem goes away?

I have tried it but unfortunately the problem persists.

[Nikhil Sapre]

What version of MATLAB are you using?