Support

For some reason Joomla thinks that the Admin Tools package extension is installed and tries to perform an update. During the update it cannot find the table jhuy8_admintools_filescache or at least its admintools_filescache_id column. Essentially, Joomla's database seems to be out of sync with what is actually installed on your server's disk and what is installed on your server's database. This is extremely rare but can happen if you had a previous update which partially failed, or restored the database (but not the site files!) from a backup which had an older version of Admin Tools. Joomla performs updates on the database based on the information it stores in the database, without checking if what it's trying to do is right (the extensions updates are NOT idempotent, a fact I have criticised since circa 2009).

We will have to remove everything related to Admin Tools manually to help Joomla get everything back in sync. To do that, we have to do a little bit of fiddling in the database.

IMPORTANT: If you have a recent backup of your site it's a better idea to restore that backup instead of following the instructions below.

Please try removing all installed extensions which contain Admin Tools in their name.

Then, delete the database tables whose name starts with jhuy8_admintools_ 

Check the jhuy8_extensions table. Look for an entry with element=com_admintools and note down the value of the extension_id (it's a number, e.g. 1234)

In the jhuy8_schemas table find the entry whose extension_id value matches the value you found above. If there is no such entry or you didn't find an extension_id in the previous step you can safely skip this.

Now you should be able to install Admin Tools from scratch.