In SPO/E Core, administrators can restrict modifications to documents by applying secure privileges. This way, only privileged users can check out, check in, re-classify, and update a document securely.
If you need to edit a document securely in the Desktop Client, use the Check Out (Secure) command to check out the document. After you have edited the document, you can check in the document to the Desktop Client by using the Check In (secure) command.
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