In-place upgrade of a Themelr template (Joomla)

From: http://answers.themler.io/articles/173620/how-to-fix-the-error-after-updating-to-joomla-3-9

How to Fix the error after updating to Joomla 3.9

If you updated to the latest version and the following error appears when you try to launch Themler please follow the instruction below:

Fatal error: require_once(): Failed opening required '[...]/administrator/includes/toolbar.php' (include_path='.:/usr/lib/php7.2') in [...]/templates/[theme_name]/app/index.php on line 25

  1. Open theme folder on the server: www/Joomla_directory/templates;
  2. open /app folder;
  3. open index.php for editing in any html or text editor;
  4. find the line
    require_once JPATH_BASE . DS . 'includes' . DS . 'toolbar.php';
    and replace it with the following line:
    $prefix = version_compare(JVERSION, '3.9', '>=') ? 'sub' : '';
    require_once JPATH_BASE . DS . 'includes' . DS . $prefix . 'toolbar.php';
  5. open /app/start folder;
  6. open data.php file for editing and follow step 4;
  7. open manifest.php file for editing and follow step 4;
  8. start Themler.

How to reset Joomla (admin) passwords in MySQL

Oh joy, you lost the admin password. Now what?

If the admin user is still defined, the simplest option is to change the password in the database to a known value. This requires that you have access to the MySQL database using phpMyAdmin.

“what, no hacking?”, I hear you say. No. Again, you need access to the MySQL database by using phpMyAdmin.

  1. Navigate to phpMyAdmin and select the database for the Joomla site in the left-hand drop-down list box. This will show the database tables on the left side of the screen.
  2. Click on the table “jos_users” in the list of tables.
  3. Click on the “Browse” button in the top toolbar.
  4. Find the user whose password you want to change and press the Edit icon for this row. A form will display that allows you to edit the password field.
  5. Copy the following value into the password field and press the Go button.
    d2064d358136996bd22421584a7cb33e:trd7TvKHx6dMeoMmBVxYmg0vuXEA4199
    
  6. At this point, the password should be changed to “secret”.
  7. Log in with this user and password and change the password of this user to a secure value.