Upgrading Elgg

Upgrade Instructions

Before upgrading, back up your Elgg database and code. Disable non-core plugins.
Download the new version of Elgg from elgg.org.
Overwrite your existing Elgg files. Any modifications should have been written within plugins, so that they are not lost on overwriting. If this is not the case, take care to maintain your modifications.
Visit http://your-elgg-site-URL/upgrade.php
Copy htaccess_dist to .htaccess, replacing your existing version. If you modified the default .htaccess, be sure to move your modifications over to the new one.

It is best to try out a new version on a test site before doing an upgrade
As you turn your plugins and theme back on when the upgrade is finished, be careful to note problems with those plugins so that you can report them to the plugin authors.