Sometimes it happens, that Joomla! system does not remove all the component data from system while uninstalling component. In such case, you can do it manually in your database. E.g. in phpMyAdmin. Before doing this, be sure you understand basic features of SQL and you know what you are doing, see following example for Phoca PDF:
-- Experts only -- Run these queries in your phpMyAdmin -- Manual removal of Phoca PDF component from Joomla! database -- Change the #__ to your Joomla! prefix, e.g. #__extensions to jos_extensions DELETE FROM `jos_schemas` WHERE `extension_id` = (SELECT `extension_id` FROM `jos_extensions` WHERE `type` = 'component' AND `name` = 'com_phocapdf'); DELETE FROM `jos_extensions` WHERE `name` = 'com_phocapdf'; DELETE FROM `jos_assets` WHERE `name` = 'com_phocapdf'; DELETE FROM `jos_menu` WHERE `type` = 'component' AND `title` LIKE '%com_phocapdf%'; DELETE FROM `jos_session` WHERE `data` LIKE '%com_phocapdf%';
Sometimes happens, that component menu links are not displayed in Joomla! administration, try to run these SQL queries:
-- Manual publishing of Phoca PDF component menu items in Joomla! administration -- Change the #__ to your Joomla! prefix, e.g. #__extensions to jos_extensions UPDATE `jos_menu` SET `published` = '1' WHERE `type` = 'component' AND `title` LIKE '%com_phocapdf%'; UPDATE `jos_menu` SET `component_id` = (SELECT `extension_id` FROM `jos_extensions` WHERE `type` = 'component' AND `name` = 'com_phocapdf') WHERE `type` = 'component' AND `title` LIKE '%com_phocapdf%';
If you are removing the component manually, it is possible that files and folders of this component will remain on your server. Then connect to your server with FTP client (or use Phoca Commander) and delete the folders of the extensions which you want to remove (be aware: do not remove all other needed parts of the system, you should have Joomla! filesystem knowledge to remove files from Joomla! filesystem).
For example, if you want to remove Phoca PDF component, delete these folders:
- components/com_phocapdf
- administrator/components/com_phocapdf
- media/com_phocapdf
and these files:
- language/en-GB/en-GB.com_phocapdf.ini
- language/en-GB/en-GB.com_phocapdf.sys.ini
- administrator/language/en-GB/en-GB.com_phocapdf.ini
- administrator/language/en-GB/en-GB.com_phocapdf.sys.ini
Sometimes it is needed to empty main tmp folder (you can find it in root of your Joomla! installation, it is temporary folders, so there should not be any important data)
If you will delete the folders listed above, allways delete only the last folder in the path, so if there is a path: administrator/components/com_phocapdf, you should delete only the com_phocapdf folder.
If folders of the component are not removed, Joomla extension manager can run update instead of install. This is why following folders needs to be removed:
- components/com_phocapdf
- api/components/com_phocapdf
- administrator/components/com_phocapdf
The Joomla extension manager examines these three folders and if at least one of them exists, it runs an update instead of an installation and an error occurs during a new installation. So, very often it happens that the component folder remains in the api folder and this then leads to the impossibility of installing the component.