Here is the process to restore the user.
1. Open the IP Office configuration.
2. Click on the user tab.
3. Save the User extension by change the extension Example 351 to Ext 351.
4. Click on the extension tab and find Ext 351 and change the Ext to a non used Ext like 600.
5. Send the configuration to the IP Office with a merge option.
6. Pull the configuration from the IP Office.
7. Click on the Extension tab and find 600 and change back to 351.
8. Send the configuration back to the IP Office.
9. Pull the IP Office configuration and click on the user tab and renumber 600 back 351.
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