Question

Why is restricted mode turned on by network administrator.

Answer 1

Answer: So students won't look up inappropriate things on their computer

Explanation: The schools locks down some sites so children won't get distracted in school.

Answer 2

For example, the DNS settings on your routers might be causing this, your network administrator might have this enabled at their end or if you installed a new add-on in your browser then it might be causing to force these settings and thus preventing the user to change this option.