I'm Lucy, and I'd be happy to answer your questions today.
The first step is to make reasonable efforts to locate the man. That could include any or all of the following: Google searches, social media searches, pulling statements from any joint accounts to get the address, calling the last known telephone number, sending mail to the last known address (unless she knows he hasn't lived there in several years), reaching out to any family members she can contact to ask for his location, and talking to any mutual friends or acquaintances that might have any information. She could also check the state death records and the Social Security Death index, just in case.
Once she's taken steps intended to find him and come up with nothing, she can file the Complaint for Divorce along with a Motion for Service by Publication. She'll explain to the judge all the things she's done to locate this man. Then she can ask for permission to publish notice of the suit in the local newspaper. The notice will run for a couple of days a week, usually for a few weeks, and the husband is legally considered to know about the case after that time period is up. Then the case would proceed the same as if the man had been handed the papers.
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