MATLAB: Do I receive a java.lang.​IllegalArg​umentExcep​tion error message when starting MATLAB Compiler

MATLAB Compiler

Why is it that when I start up MATLAB Compiler, I get the following error message: 
 
Exception in thread "AWT-EventQueue-0" java.lang.IllegalArgumentException: This collection does not allow clients with duplicate names
at com.google.common.base.Preconditions.checkArgument(Preconditions.java:93)
at com.mathworks.desktop.client.UniqueClientCollection.check(UniqueClientCollection.java:53)
at com.mathworks.desktop.client.UniqueClientCollection.add(UniqueClientCollection.java:47)
at com.mathworks.toolbox.compiler.desktop.DeploytoolToolstripTab.initializeToolstrip(DeploytoolToolstripTab.java:55)
at com.mathworks.toolbox.compiler.desktop.DeploytoolToolstripClient.loadingFinished(DeploytoolToolstripClient.java:128)
at com.mathworks.project.impl.ProjectGUI$3$1.run(ProjectGUI.java:387)
at java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$200(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)

Best Answer

This may be an issue with either your toolbox cache not being up to date or having insufficient privileges to your pathdef.m file. 
Try running the following commands in MATLAB:
>> rehash toolboxcache
>> savepath
Afterwards, try starting up MATLAB Compiler again. If the above commands return with any error about permissions error with the pathdef.m file, try placing the file in your MATLAB working directory. 
The pathdef.m file should be located in your $MATLABROOT\toolbox\local (for Windows) or $MATLABROOT/toolbox/local (for macOS and Linux).
$MATLABROOT being your MATLAB installation directory.  
 
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