---
sourceDocument: Xanadu Build or modify applications
sourceDocumentLink: https://www.servicenow.com/docs/r/xanadu/application-development

 Release :

    - xanadu

ft:locale :

    - en-US

ft:publication_title :

    - Xanadu Build or modify applications

ft:clusterId :

    - cadev

bundleId :

    - cadev

workflow :

    - Development, Data, and Analytics


---

# Application file protection policy

# Application file protection policy {#ariaid-title1}

* Release version: Xanadu
* 
* Updated August 1, 2024
* 
* ![](https://www.servicenow.com/docs/portal-asset/ico-clock) 1 minute to read

A read-only protection policy prevents anyone from modifying an application file or its
related record.

Some application code shipped with the ServiceNow system requires special protection. Only a ServiceNow employee can alter the protection policy and then modify the application file or its related record. A ServiceNow employee cannot edit protected files without changing the policy designation first.

To prevent customizations from being overwritten by system upgrades, the upgrade process
automatically skips changes to customer-updated records. If you modify an application file or
related record that is later designated as Read-only in an upgrade, the
application file maintains the default protection policy of Write. You keep the
existing modifications and can continue modifying the records.  
Note:  
Reverting a customized file to its baseline state causes the record to inherit the new protection policy as well. For example, a record going from a Write protection policy to a Read-only protection policy.