If you are using cPanel, perhaps you can try Account Level Filtering.

ca47, this is custom code modification.

I guess that all students have email addresses in  studentname@universityname.com format? (like jane@auca.com, bill@auca.com, bob@auca.com).Where the part after @ is always one and the same for all addresses?

If this is the case you can just add a new check/validator to the "Email" field, so that only emails that end with @auca.com, for example, will be able to register. All other emails will result in "Incorrect email format" error.

Search for "email pattern", "email validation  php" or "regular expressions for email validation" keywords in google to find the solution.

okay thank you. will try it :)

As Aliia mentioned, I also would suggest to use email patters if the email domain does not change.

If it changes, you have get more detailed in to the core.

The filter that I mentioned is applied only to your email account and has nothing to do with your website. If you want to modify the registration form of your website not to accept each email account, you will have to contact a local developer to assist you further with that. I found it to be a development issue.

I rushed here to post this here, but Aliia has already made you wise to it.

My apology  for the wrong suggestion.