Due to changes in the packaging format and / or issues in the updater, you cannot update automatically from Akeeba Backup for WordPress versions 1.0 through 1.8.2 (inclusive) to version 1.9.0 and beyond. You will have to do that manually.
Heads up! You must NOT uninstall or deactivate the plugin before the update. Doing so may result in loss of your backup settings and / or your backup archives. Instead, here's what to do:
akeebabackupwp.
akeebabackupwp folder into your site's
wp-content/plugins/akeebabackupwp
folder, overwriting your existing files, using FTP or SFTP.
Please note that the name of the folder on your site may be different than akeebabackupwp,
e.g. akeebabackupwpcore, akeebabackupwp (1) or something similar. It depends on how
you installed the plugin.
You will only need to do this once, upgrading to version 1.9 or later for the first time.
Akeeba Solo and Akeeba Backup for WordPress 1.9 are compatible with PHP 5.3.04 and later versions, including 5.4, 5.5, 5.6 and the newest version of PHP, 7.0. We'd like to remind you that most third party software which can be backed up by our software do not support PHP 7 yet. As a result we can't guarantee a trouble-free restoration or tha the restored site will work on PHP 7 as this depends entirely on the software powering your site.
Note: there is no such thing as PHP 6. PHP versions jumped from 5.6 to 7.0. Why? Well, it's a long story. TL;DR: It doesn't have to make sense, just accept it.