In your Student installed MATLAB, you are receive this message 'Your Matlab license will expire in XX days.':

The message appears because our institute has a contract with MATLAB for a campus-wide license. Every year it is necessary to validate that you are still a student or university member and here is how it goes:

Start Matlab and click on the HOME-tab and then on the Help-button (below the question mark)
A drop-down menu appears: choose > Licensing > Activate Software

Allow Matlab to make changes on your computer
(if not possible start Matlab in administrator mode)

Choose: Activate automatically using the Internet (recommended)
click on next

Choose: Log in to my MathWorksAccount: type in your email address and your password.
click on next

Select the license you want to renew, e.g. Academic License (Uni XY).
click on next

A prompt appears:

"You must verify your university login information before you can proceed.
Click here to complete the verification process from your university's login portal."
> Click on the blue words "click here" to follow the link to your university/institute website.
Login with your university/institute account in order to confirm your membership.
aftwards your forwarded to the MathWorks page displaying: "Verification succesfull"

Go back to matlab and click on OK in the promt window.
click on next

Type in the name of the Windows/Mac/Linux user for whom the license should be valid
(depending on the contract the license is only valid for one or two users).
click on next

This information will be sent to MathWorks.
click on confirm

Activation is complete > click on Finish.
Close your browser window, close Matlab.
Your license is now prolonged.

If the message "Your Matlab license will expire in XX days" still appears after restarting Matlab,
click on the Help button (in the HOME-tab) and choose Licensing -> Update current License from the drop-down menu.

After the next restart of Matlab the message should be gone.