Why can't I claim my 17 year old son as a dependent?

My 17 year old son is a senior in high school.  Easy guide tells me that I cannot claim him as a dependent.  Why not?
    Are you at the screen that asks if your son provided more than 50% of his support?  and then below that is says

    "If yes, you cannot claim [his name] as a dependent. Explain this

    If that is the screen you are at you will see two buttons marked YES and NO further down. If your son really did provide more than 50% of his support you have to answer YES and you can't claim him as a dependent. But if he did not provide more than 50% of his support and you did provide more than 50% of his support then you can answer NO and go onto the other questions that help determine if you can claim him as a dependent.
    • i still dont understand what u are talking about
    go under deductions and credits / You and Your family / Earned Income Credit / push update / It ask if you want to work on this credit anyway put Yes. If you earned more then 48,362.00 dollars you can not claim your child on your taxes..
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