Since OData provides access to information in GP, it's important to ensure that this access is secure. Dynamics GP uses active directory connected to GP users and SSL to provide secure access to data. OData specific roles and tasks are used to ensure that users can only access data they have authorization for.
For companies that have upgraded to Dynamics GP 2016 from a previous version, the new security roles and tasks are missing. There is a SQL script that needs to be run to add the new roles and tasks. The script is available at http://azrcrv.co.uk/1bVUnr
New installations of GP 2016 will include these roles and tasks as part of the installation. Only upgraded versions require running the script.