Your version of WordPress is very old. We have only tested our software with WP 3.8, 3.9 and 4.0. However, I am not sure whether this is an issue with your WP version. Is it possible to try installing Akeeba Backup on a WordPress 4.0 site on the same server and let me know if you get the same error message?
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!