That is not proper notice. I suggest you hire a real estate lawyer if you want it done right without having to keep starting over as you now have to do.
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Start with the basics, asking him to leave. If he refuses, then consult a landlord tenant attorney for procedure on his removal. You must do thing properly to avoid a lengthy holdover.
I agree with Mr. Rothstein. I read his answer and your comments back & forth. Unfortunately, your roommate has rights and unless you bring a proper eviction, you will never get him out. Sit with a local attorney and spend the few bucks you will need to do this right. The longer you wait and the more you dilly-dally will just prolong your agony.
I may be guessing or not licensed in your state. No atty/client relationship exists. I earn my living collecting points for "helpful" answers.