The Maintenance section has several functions:

1. It performs a detailed permissions check on all the dadaIMC directories, informing you if some directories are not writeable (but should be). You can correct any errors manually, or use the "changeperms.sh" script in the /docs/ directory to set them all at once. Be sure that "changeperms.sh" can be executed (750 or similiar permissions) before running it!
2. It checks for PHP "safe mode" settings, and attempts to locate the path to various UNIX executables used throughout dadaIMC.
3. It can delete old database tables and dadaIMC backup files, and can delete the dadaphp.log.
4. It cleans up obsolete records from various places in the database. Sometimes, when users are deleted, they may leave behind ownership records for other database content. The maintenance script will automatically delete obsolete records if those checkboxes are checked.
5. By checking boxes associated with modules, you can delete all the cached files for that module. Normally, this is performed by cronjobs, or automatically when the content has changed, but under some circumstances (modifying display files, for example), you may need to manually clear the cache.