Authorisation error when deleting and unpublishing a document

I am using Umbraco 7.1.4

I get the following error when trying to delete a document

Authorization error: Unauthorized access to URL: /umbraco/backoffice/UmbracoApi/Content/DeleteById

and this error when unpublishing

Authorization error: Unauthorized access to URL: /umbraco/backoffice/UmbracoApi/Content/PostUnPublish

We can create and save documents fine.

This is only occuring on the live server. It works properly on local and staging servers, I can't see any differences in the settings between the setups. I have looked at the permissions and read only status on the files etc. I can access the API's to check they are working.

What would cause this error to occur?


This is a companion discussion topic for the original entry at https://our.umbraco.com/forum/54560-authorisation-error-when-deleting-and-unpublishing-a-document