Noob question: Why can't I access reddit on school wifi without first going to a different reddit client?

To get on reddit on my personal computer at school, I have to first open MSOutlookit, a non-official reddit client, and then I can open the official Reddit page. When I don't go to MSOutlookit first, I'm unable to get to Reddit.

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P.S. I'm on Reddit during my free period, don't worry mom.