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Log in as an admin to your Jira Data Center instance
Navigate to Administration > Project Team > Import From Cloud page
For Project Team Exported Data From Cloud, choose the JSON file generated previously
For Jira Cloud Exported Entity XML File, choose the entities.xml file extracted from the Jira backup for Cloud archive
You can check the "Merge data" Data option if you have imported the data once and want to re-import a file that now contains additional user custom fields. This will allow importing the process to import the new custom fields and their associated user values.
Click Start Import to begin the import process
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