Support

Hello,

System Restore Points can be used to keep a backup copy of the extensions you are updating. The idea is this: whenever you try to update an extension, Akeeba Backup kicks in and tries to back up only this extension's files and database tables. It will then hand over the execution to Joomla!'s extension installer to complete the installation.

So, this will only work for extensions already installed on your site, when you try to update them.

There is one catch: Akeeba Backup doesn't really know which files and database tables belong to the extension you're updating. Joomla! does not have a standard. There are some guidelines, but developers can choose to ignore them. Therefore, Akeeba Backup tries to guesstimate (it's 50% guessing and 50% assumptions) this information in order to produce the System Restore Point. Most major extensions work flawlessly, some of them not so well, so it's basically a hit-and-miss thing. If you want to be 100% certain that an extension update won't screw up, take a full site backup before installing it. If you forget, there's an 80% chance that the System Restore Point will be able to roll back your extension to its previous state. But, remember, there's also a 20% chance it won't work.

Obviously, had Joomla! enforced strict naming standards for folder and –most importantly– table names, the percentage of extensions which can be rolled back would be close to 100%.