There was a missing line in the Backup on Update plugin published with Akeeba Backup 7.5.0.1. This plugin needed to use the common library we use with all of our software but did not load it. This issue was masked in development and testing by the fact that other plugins, either Akeeba Backup's or of our other software, could be loading said library if they were set up to run before the System - Backup on Update plugin.
The missing line has been added to the plugin and a new version, Akeeba Backup 7.5.0.1, has just been released.
If you are unable to access your site's backend please remove the folder plugins/system/backuponupdate. Then please upgrade to Akeeba Backup 7.5.0.1 which addresses the issue.
Nicholas K. Dionysopoulos
Lead Developer and Director
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