I do not know if it works, but there is a company that makes a box that you plug in between your landline phone set and the wall jack and it has a program that just automatically blocks any outgoing 411 phone call. It costs about $80 (in our case, less than a month's worth of the amount of calls being made). it is called "411 blocker" and available from hqtelecom.com and can be ordered online. We just ordered it. If it does not work, it has a 30 day return policy.
Do you have traditional landline service or FiOS Digital Voice?
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