Description of my issue:
After updating Akeeba Backup to 4.1.2 I saw the warning about JSN PowerAdmin. Sure enough both Akeeba Backup and Admin Tools no longer appear in my Components menu even though they are installed and published.
I tried uninstalling JSN PowerAdmin and the uninstall appeared successful. However, even after clearing cache, browser cache, logging out of administrator and then logging back in Akeeba Backup and Admin Tools still do not appear in the components menu.
Is this related to the warning you recently added? Is there some way I can manually repair what has gone wrong? If you need admin access to the site I will be happy to provide.
Thanks.