There is a legal answer to most questions and a practical answer. You are not required to meet and confer at this point. However, and many judges have different attitudes about this, you may find that you get better results with your next motion if you show that you did try to get your opponent to comply with the court order-even if it is just a quick email or letter giving him a short time period to comply and letting know what your next step is if you don't obtain compliance. Your next step would not be another motion to compel. This time, you would bring a motion for sanctions as a result of his failure to comply with a court order. Potential sanctions are terminating (the plaintiff's case is dismissed or the defendant's answer is stricken although this is unlikely at this point), issue sanctions (he can't introduce certain evidence or documents at trial), or further monetary sanctions. You should consult with an attorney to obtain more details regarding the art of obtaining sanctions.
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I agree that a full meet-and-confer is not necessary, but a reminder letter with a statement that you will file an appropriate motion for sanctions seems to be in order.
Selecting the appropriate sanctions to seek is not easy. You would be wise to engage in some "litigation coaching" to help you strategize the motion, and perhaps help you draft it.