License Error while running Yolov4 object detector

I'm getting the following error message once I run the Yolov4 object detector. Also, the training data is not saved.

Error using vision.internal.cnn.validation.checkDetectionInputImage

License checkout failed.

License Manager Error -15

Unable to connect to the license server.

Check that the network license manager has been started, and that the client machine can communicate with the license server.

Troubleshoot this issue by visiting:

https://www.mathworks.com/support/lme/15

Diagnostic Information:

Feature: Video_and_Image_Blockset

License path:

Licensing error: -15,0.

Error in yolov4ObjectDetector/parseDetectInputs (line 649)

[sz,params.DetectionInputWasBatchOfImages] = vision.internal.cnn.validation.checkDetectionInputImage(...

Error in yolov4ObjectDetector/detect (line 440)

params = parseDetectInputs(detector,I,varargin{:});

How to resolve this issue.

Answer 1

[Walter Roberson]

It sounds as if you are configured for multiple license servers, and the license server you normally use does not have a license for you for Computer Vision Toolbox. When MATLAB attempts to find a license for Computer Vision Toolbox, it attempts to contact the other license servers that are configured -- and fails in doing so. (Possibly the additional license server is beyond a disconnected VPN)