Taken from the original plugin page:

Admin can configure (in the plugin settings) if site is down for maintenance. Optional extra information about the downtime can also be entered there.

When in maintenance mode site is in a complete lock down. Only admins can login.

Version History: 

Version 1.8

1. Fixed compatibility with elgg installed in a sub directory.
2. Fixed javascript file version reference in maintenance index page (exposes admin login)
3. Added priority (200) to maintenance plugin system index hook to make it compatible with custom index plugin.
4. Added view default/core/account/login_walled_garden to fix compatibility with walled garden setting in elgg v1.8 (walled garden setting is in admin/advanced settings and reads: "Restrict pages to logged-in users".

(previouse version history by Jeroen)

Version History1.1- fixed: problem with maintenance plugin in combination with custom_index

1.0- first release

ColdTrick IT Solutions(c) 2009 ColdTrick IT Solutions

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