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Click the cog icon (Administration) > Manage apps > under Salesforce, select Connector for Salesforce & Jira Migration.
Read the disclaimer and click Accept to view the migration steps page.
Click the Disable button to stop any current synchronization between Jira server and Salesforce.
The green check mark confirms that the Classic Connector for Salesforce and Jira app has been successfully disabled.
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Click Step 2 - Starting the migration process from the menu on the left.