By default Archive Explorer displays preview of an item which is less than 512KB in size. In the reading pane for
a large size item, Archive Exporer displays message "This document is too big to preview, please open it instead"
To overcome this limitation create an ANSI webapp.ini (case sensitive) in the installation directory of EV (X:\Program Files\Enterprise vault\)
Add below in the webapp.ini file and restart EnterpriseVaultAppPool