I was using RetrievePrincipalAccessRequest and RetrievePrincipalAccessResponse objects to retreive user access rights on entity using entity instances. This worked until thus far when I tried to retreive access rights on custom entity.

I get the following error "The 'RetrievePrincipalAccess' method does not support entities of type 'my_entity'.

Below is the code that I am using to retreive user access rights on entities.

        protected internal static AccessRights? GetUserAccessRights(string entityName, string UserName, out Guid? UserId)
        {
            // Instantiate the service object
            OrganizationService service = new OrganizationService("MY_ORG");

            // Instantiate the context object
            PRMServiceContext context = new PRMServiceContext(service);

            if (entityName != null && !String.IsNullOrEmpty(entityName) && !String.IsNullOrEmpty(UserName))
            {
                try
                {
                    // Get the owner id of the user
                    var userId = (from su in context.CreateQuery<SystemUser>()
                                  join sur in context.CreateQuery<SystemUserRoles>()
                                  on su.SystemUserId equals sur.SystemUserId
                                  where su.DomainName == UserName
                                  select su.SystemUserId).FirstOrDefault();

                    Guid? instanceId = null;
                    switch (entityName)
                    {
                        case "contact":
                            instanceId =
                            (
                                from c in context.CreateQuery<Contact>()
                                where c.Id != null
                                select c.Id
                            ).Take(1).First();
                            break;
                        case "phonecall":
                            instanceId =
                            (
                                from c in context.CreateQuery<PhoneCall>()
                                where c.Id != null
                                select c.Id
                            ).Take(1).First();
                            break;
                        case "my_entity":
                            instanceId =
                            (
                                from c in context.CreateQuery<my_entity>()
                                where c.Id != null
                                select c.Id
                            ).Take(1).First();
                            break;
                    }


                    if (userId != null && instanceId != null)
                    {
                        RetrievePrincipalAccessRequest req = new RetrievePrincipalAccessRequest();
                       
                        //specify team or systemuser you want to get privileges for
                        req.Principal = new EntityReference("systemuser", userId.Value);

                        //specify the CRM record you want to check principal permissions for (can be any entity type)
                        req.Target = new EntityReference(entityName, (Guid)instanceId);

                        RetrievePrincipalAccessResponse resp = (RetrievePrincipalAccessResponse)context.Execute(req);
                        context.ClearChanges();

                        ParameterCollection pc = resp.Results;
                        UserId = userId;

                        return resp.AccessRights;
                    }
                }
                catch (Exception ex)
                {
                    throw ex;
                }
            }
            UserId = null;
            return null;
        }

 Please help. Thanks.