Due to an issue with Admin Tools 4.0.0.b1 to 4.0.0 inclusive, users of the Professional release must update manually to this new version.
Akeeba Backup for Joomla 5.1.2, Akeeba Backup for WordPress 1.9.2, Akeeba Solo 1.9.2 and the respective later versions no longer support integration with the Dropbox API version 1. You will need to do some manual changes to your backup profiles to use the Dropbox API version 2 integration we have made available since November 2015.
Akeeba Backup 5.0 was written from scratch. Despite testing it fully, several major bugs were overlooked and others introduced through subsequent releases.
An issue in Akeeba Backup 4.7.0 may have removed the update sites from your Joomla! installation. We have a fix for that. Please read on.