1. A system to provide data management services, wherein the system is communicatively coupled to at least one client computer and at least one third party server computer, the system comprising: a data storage system coupled to the at least one client computer via a local area network and to the third party server computer via a wide area network or public computer network, wherein the third party server computer is associated with a company or organization unaffiliated with a company or organization controlling operation of the data storage system, and, wherein the data storage system includes: at least one server computer, at least one data storage device, and a retention component configured to receive data objects from the at least one client computer, wherein the data objects from the at least one client computer are associated with a first format, receive data objects from the third party server computer, wherein the data objects from the third party server computer are associated with a second format, wherein the first and second formats differ, and apply respective first and second retention policies to the data objects in the first and second formats to store the data objects in the at least one data storage device according to the first and second retention policies, and wherein at least one of the first or second retention policies requires received data objects be de-duplicated, encrypted, or both de-duplicated and encrypted, and wherein the received data objects are not converted to another format; a data classification component configured to content index and classify the data objects in the first and second formats; a search component configured to permit searching via the at least one client computer and the third party server computer of the data objects of the first and second formats, respectively, wherein the search component is further configured to apply searching restrictions or access control based on securities policies, and without need for data agents on the at least one client computer or on the third party server computer; and, a reporting component configured to provide reports based on search results provided by the search component, wherein the data storage system is further configured to: calculate a hash value for a newly received data object, determine that the calculated hash does not match a previously stored hash for a previously stored copy of the data object, and report that contents of the data object have changed.