Since I was so far behind on the update, I just was able to update to Joomla 3.6.5 and started to update Akeeba Backup and Akeeba Admin Tools. I began with update Akeeba Backup from 5.1.2 to 5.2.5 and 5.3.4, so currently I have Akeeba Backup 5.3.4. Everything works fine.
For Admin Tools, my plan is I will update from 3.8.5 to 3.8.6 and 4.0.2 and 4.1.3. When I updated Admin Tools from 3.8.5 to 3.8.6, everything worked. Then, I update to 4.0.2, I cannot access to Akeeba Backup in the Administrator area. I got a blank gray page with HTTP ERROR 500. I reinstall 4.0.2, and still get the same result. I hesitate to jump to try to install Admin Tools 4.1.3. Please advise.
Thank you,
M