MSCRM 2011 - Retrieve Attachments by ID

// Comment
QueryExpression query = new QueryExpression

                    {
                        EntityName = ActivityMimeAttachment.EntityLogicalName,
                        ColumnSet = new ColumnSet("activitymimeattachmentid"),
                        Criteria = new FilterExpression
                        {
                            Conditions =
                        {
                            new ConditionExpression
                            {
                                AttributeName = "objectid",
                                Operator = ConditionOperator.Equal,
                                Values = {"activity/customentity ID"}
                            },
                            new ConditionExpression
                            {
                                AttributeName = "objecttypecode",
                                Operator = ConditionOperator.Equal,
                                Values = {Email.EntityLogicalName}
                            }
                        }
                        }
                    };
EntityCollection results = service.RetrieveMultiple(query);

Nicola Grillo