arrangements to settle old debts with a company

I would like to know if you do not make arrangements to settle old debts with a company. Do they ever come off your credit report? Or is the only way to get it fixed is to set up a payment plan. Thank you
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they are supposed to come in 7 years from date of last activity.
sometimes creditors find way of manipulating this date. collections and stuff
once they set up payments though they cannot SUE you for the balance. So most either sell them to collections, sue or charge you off. suit or collections are the most painful. collections is where the redating come in most times.