The Netmail software has the ability to update itself via the Updates tab in the administration console. However, when doing so, it will only update the binaries on the Netmail servers (proper). Netmail components installed elsewhere (IIS extensions on Exchange servers, Outlook add-ins on workstations, Groupwise webviewer components, etc) will not be touched. It is up to the administrator to fetch the new versions of these components and roll them out to the other servers as part of a coordinated & scheduled upgrade process.
Each upgrade of Netmail will create a new folder under C:\Program Files (x86)\Messaging Architects, prepended with an underscore, as in the screenshot below:
In there it will place backups of the configuration files (collected prior to the update), the install logs during the update, and the new versions of the auxiliary components (in \LocalSetups)
To get the latest version of these auxiliary components that match your Netmail servers, always fetch the installers from this location.