DELETE cannot be completed because others own items, try Manage Private Mode
User receives the error messages above with a REST request.
To address this issue, use the following parameters for Web Services that allows you to go into Mode Manager.
IBIRS_mode = true or false
When the value is set to true, you are placed in mode manager mode and you are able to manage someone else's private content. When the value is set to false, you are returned back to normal mode and you can only manage your own private content.