Yes, you can be served at your workplace. No, there is no obligation to give process servers any access to you while at work. Just keep in mind that after several diligent attempts to serve you, the plaintiff can substitute serve you by dropping the summons and complaint at your place of work and mailing you the documents. If that becomes impossible, they can get an order from the court to serve you by publication in a newspaper. In other words, you are not going to avoid being in a lawsuit by avoiding service. It often makes sense to simply make it easy to be served because if you lose, the costs being incurred to make the attempts to serve you will be costs assessed against you in a post trial judgment.
Good luck to you.
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