[Solved] HELP - Can't log in to Admin - After using Akeeba Admin Tools

[BodgeIT]

I had some login issues where even after putting in username & pass, it stayed on the login screen.
I thought I'd uninstall and reinstall.  Uninstall failed as it couldn't delete a folder, so I did that for it.  Tried to reinstall and still had same issue.  Noticed that the tables hadn't been deleted fr4om the database, so I uninstalled again, then deleted the tables in the database(didn't have any data in them yet). Now when I try to install, I get an error saying "Incorrect Install file" and sends me here: http://docs.joomla.org/Incorrect_Install_File
Install reports success but when I try to go to Wordpress to configure, I get a 500 error and an error about table not existing.

How can I reset the install and start from scratch?

OK, managed to recover tables from backup and have imported them back in.
Now I'm back to my initial problem...Can't log in to back end of WP.

[Andy]

Do you have both the user plugin and the authentication plugin installed and enabled?

[BodgeIT]

Yes both enabled.
I think, this issue came after changing the prefix using Akeeba Admin Tools but cant testify to that.  I've checked all the tables in the database and they appear to be OK.
Anything you can suggest?

[Andy]

Changing the table prefix could likely break it.   Look in the table jos_wp_options and skim the data for instances of your old prefix.

Kindest regards,

[BodgeIT]

Hi Andy,
Sorry for the delay in responding.  Found 1 entry in the table(jos_wp_user_roles) but changing it hasn't helped my login issue. 
I think the best option for me now is to totally uninstall it and initiate a fresh install.  How do I do that so that the installer creates the tables during the install process?

EDIT:
OK, found some more jos_ entries in what was jos_wp_usermeta
Changed all these too although like the other entry above, they relate to tables that aren't in my system such as jos_wp_user_user_level & jos_wp_user_capabilities.
I checked against the tables in a standard Wordpress install and these tables aren't present there either.  I imagine they're some sort of virtual table or something?

Oh yeah and changing all these to my new prefix didn't fix my issue.

EDIT 2:
OK, I created a new super admin to see if that would get me access and it did.  I then realised I had also changed the SuperAdmin User ID using the Akeeba Admin Tool.  This creates a new super admin with a new random ID and changes the login of the old super admin and disables it.  It seems this doesn't get sync'd to WP(can't change the logins in WP).  When looking in the list of users for WP, I had two users with login "admin".  I deleted the one I didn't want and bingo, back in business.

Definite issue there with Akeeba Admin Tools, maybe useful to have a warning somewhere.  I'll drop them a line too, they may wish to provide a warning to their users too.