Why does 'Help' Documentation in MATLAB R2020a not work when the Proxy server is enabled?

The recent install of the R2020a version of MATLAB is blocking the request when trying to open a documentation using 'Help' with proxy server as enabled.

Answer 1

[MathWorks Support Team]

1. As an initial troubleshooting step, regenerate preferences using "restoredefaultpath" and "rehash toolboxcache". Refer to the following MATLAB Answers post for more information:

https://www.mathworks.com/matlabcentral/answers/99625-how-do-i-regenerate-my-matlab-preferences

Move to step 2 if this does not resolve the issue.

2. Does the following command run from the Command Window with proxy server enabled? This step is to check if MATLAB's Web preferences are not routing through the System Web Browser.

>> web("https://www.mathworks.com/help/releases/R2020a/matlab/ref/plot.html");

If the above command runs without error, move to Step 3. If the command throws an error, there is a possibility that the proxy server is not connected. The proxy server can be configured and tested by following the steps in the below MATLAB Answers post:

https://www.mathworks.com/matlabcentral/answers/99719-how-can-i-configure-my-proxy-server-settings-within-matlab

3. Change the help browser renderer by following the below MATLAB Answers post and observe if this resolve the issue:

https://www.mathworks.com/matlabcentral/answers/385268-how-do-i-change-the-renderer-for-the-help-browser

4. If none the above steps help, check to see if a fresh install of MATLAB R2020a with proxy enabled resolves the issue.

5. As a last resort, download the attachment 'matlabwindowjava.jar' and use it to replace the existing JAR file present in the following location, where <matlabroot> refers to the location MATLAB R2020a is installed:

<matlabroot>\java\jar\toolbox\matlab

MATLAB needs to be restarted after replacing the JAR file with the attachment.

Answer 2

[Delprat Sebastien]

I'm using Matlab 2024a. I performed all the test listed here and the documentation windows remains empty. Modifying the jar file did not change anything.

My organization does not let us access internet without a proxy. All our browser & other software (git, etc) works with this proxy.

It is not clear to me why Matalb can access the internet (i.e. the "test proxy" button allows to check that it works, the web command above works) but not the documentation.

Could you please help me with this?