Matlab engine: License Checkout Failed

I'm trying to figure out why I'm getting a License Checkout Failed when running Matlab Engine from Java. I have this very simple Matlab script:

function [] = Test()
x = [1 2 3 4 5];
y = [ 4 6 8 5 3];
 mdl = fitlm(x,y);
 mdl
end

fitlm requires the Statistics_Toolbox. I can run the above script without issues from the Matlab (version 2019b) desktop application. But when I run the same script through the Matlab engine I get

Exception in thread "main" com.mathworks.engine.MatlabExecutionException: Test()
    at com.mathworks.engine.FutureResult.get(FutureResult.java:64)
    at com.mathworks.engine.MatlabEngine.eval(MatlabEngine.java:349)
    at xxxxxxx.main(Test.kt:11)
Caused by: com.mathworks.mvm.exec.MvmRuntimeException: License checkout failed.
License Manager Error 0

Troubleshoot this issue by visiting: 
https://www.mathworks.com/support/lme/R2019b/0

Diagnostic Information:
Feature: Statistics_Toolbox 
License path: C:\Users\xxxx\AppData\Roaming\MathWorks\MATLAB\R2019b_licenses;C:\Program Files\MATLAB\R2019b\licenses\license.dat;C:\Program Files\MATLAB\R2019b\licenses\network.lic 
Licensing error: 0,0.
    ... 3 more
com.mathworks.mvm.exec.MvmRuntimeException: License checkout failed.
License Manager Error 0

I then tried setting environment variables. I tried

 MLM_LICENSE_FILE=[e-mail]

but then I get License Manager Error -39. I tried again, with

MLM_LICENSE_FILE=[e-mail]

(which matches the port in my network.lic file) and I got License Manager Error -59.

Please help! Why am I able to get a license when using the desktop app, but not when using the engine through Java?

Answer 1

[Walter Roberson]

• error -39: you or your host are not listed in a group license https://www.mathworks.com/matlabcentral/answers/98895-why-do-i-receive-license-manager-error-39 ; or flexlm bug with INCLUDE_BORROW https://www.mathworks.com/matlabcentral/answers/93927-why-does-include_borrow-cause-error-39-with-specifed-features
• error -59: license port number already in use https://www.mathworks.com/matlabcentral/answers/92542-why-do-i-get-license-manager-error-59-when-starting-the-license-manager (that would be something you would see on the server side when you tried to start the MLM license daemon)

[Jacob Heller]

@Walter Roberson I was able to figure out the literal meaning of these errors, but I still don't understand why I would be getting these issues when using the engine if the desktop app has no issues.

[Walter Roberson]

For the error -39 I would look in the flexlm logs to see which user and host are being used to access to MATLAB license.