Express Server keeps an archived history of configuration files. These files include spatial indexes, overviews and databases and can be found in timestamped folders in your installation directory. A configuration file is archived each time you publish changes. This archive can grow large over time and it is recommended that you periodically delete unneeded archives.
Express Server stores the configuration archive in the working directory. By default, the Express Server working directory is in the following location:
<Express Server installation directory>/ImageServer/var/data
TIP:You can easily access and restore archived configurations using the Express Server Manager (see Restoring an Archived Configuration).