To rebuild one or all of your data files in System Five, use the file check utility. This can be accessed from "Setup Tools" - "Utilities" - "File Check"
Once you go into the file check utility, you will be prompted to have a backup before proceeding. Then, you will see if there are any active users in the system. You cannot proceed if there are any users logged into the system. If no users are logged into System Five, The File Check utility will show all of your data files with indications on the left side noting if the file is ok or needs rebuilding. You can select the individual file in question and choose to rebuild it, or if you want to rebuild all of your data files, choose the option to Rebuild All Data Files:
Once complete, you will be prompted to restart System Five. Please see the following short video on rebuilding data files in System Five.
Video source: faq:file-rebuild-sample.flv