Why does the MATLAB 2017a Mac installer crash throwing an error about java.lang.​​NullPoint​e​rExcepti​on​Compone​nt and SizeAggregator in the log file?

I have MacOS 10.12.5 and I have 2016b installed already. I tried to install 2017a but this is the error I got:

    (Jul 04, 2017 21:36:48) java.lang.NullPointerException
  at com.mathworks.install.ComponentSizeAggregator.add(ComponentSizeAggregator.java:13)
  at com.mathworks.install.ProductInstallerImpl.downloadProducts(ProductInstallerImpl.java:143)
  at com.mathworks.install.ProductInstallerImpl.installProducts(ProductInstallerImpl.java:81)
  at com.mathworks.install.InstallerImpl.install(InstallerImpl.java:113)
  at com.mathworks.installwizard.model.InstallTask.execute(InstallTask.java:46)
  at com.mathworks.installwizard.model.AbstractBackgroundTask.execute(AbstractBackgroundTask.java:38)
  at com.mathworks.installwizard.model.AbstractTask.call(AbstractTask.java:74)
  at com.mathworks.installwizard.model.AbstractTask.call(AbstractTask.java:24)
  at com.mathworks.wizard.worker.WorkerImpl.doInBackground(WorkerImpl.java:24)
  at javax.swing.SwingWorker$1.call(SwingWorker.java:296)
  at java.util.concurrent.FutureTask.run(FutureTask.java:262)
  at javax.swing.SwingWorker.run(SwingWorker.java:335)
  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
  at java.lang.Thread.run(Thread.java:745)

(Jul 04, 2017 21:36:48) Error: The application encountered an unexpected error and needs to close. You may want to try re-installing your product(s). More information can be found at /var/folders/r0/r4rx7j0x6mngw7v8ypz4xdkr0000gn/T/mathworks_username.log (Jul 04, 2017 21:36:52) Exiting with status -1 (Jul 04, 2017 21:36:53) End - Unsuccessful.

Could someone help me to figure out what should I do to solve this issue?

P.S. I don't have any folder named MathWorks under Downloads.