There are safeguards in place that require you to inform your ex of the default judgment. Example: The motion for default and a copy of the default judgment must be mailed to her - proof of those mailings are filed with the court. After the judgment for divorce is entered, the time to vacate is 30 days. After 30 days, she can still move for it, but it's very very difficult to get.
She can move to vacate the judgment up to 30 days following its entry if everything is on the up and up.
She has two years to try to set the judgment aside for certain reasons, and she has forever to set it aside if there was fraudulent concealment of pertinent financial information.
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