404 error component not found

[santinox]

Hello guys.
Use for 10 days phocaguestbook, it has always worked well. Today he decided to stop doing it.

I click my phocaguestbook from the site and gives me a page with 404 error in red. I decide to go to the backend to see what happened, I go on components and then Phocaguestbook, also in the backend it gives me the following error: "404 error component not found".
In despair I decided to uninstall the component of the extensions list, receiving this error:

"Caution
JInstaller:: Install: The XML setup file could not be found
JFolder:: delete: Folder could not be deleted. Path: / members / chatamicizia / administrator / components / com_phocaguestbook
JFolder:: delete: The path is not a folder. Path: / members / chatamicizia / components / com_phocaguestbook
Component uninstallation: it is not possible to uninstall. Remove manually"

I decide then to manually remove the component folder inside the components folder of joomla via ftp, try again to uninstall, nothing, same error, moreover the component's entry remains in component list.
I try to force an installation of the phocaguest component by receiving this error:

"Caution
JInstaller:: Install: The XML setup file could not be found
Copy failed: /membri/chatamicizia/tmp/install_5ad8aa243f69f/access.xml to /membri/chatamicizia/administrator/components/com_phocaguestbook/access.xml
JInstaller:: Install: Failed to copy file /membri/chatamicizia/tmp/install_5ad8aa243f69f/access.xml to /membri/chatamicizia/administrator/components/com_phocaguestbook/access.xml
Update component: unable to copy administrative files."

I have read that a solution could be cleaned up manually from the SQL database, the site. https://www.phoca.cz/documents/16-jooml ... m-manually, but I did not understand how I should do it.

At this time, the "phocaguestbook" component folder is manually removed via ftp, however the extension list appears, and it does not allow me to uninstall or install the component.

I do not know how to solve this problem, I need this component on my website. Please can someone help me?
Thx

UPDATE:
I tried to manually delete these too:
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
I try to install the Phocaguestbook component and I now receive the following error:

"Caution
JInstaller:: Install: SQL error Duplicate entry '1' for key 'PRIMARY'
Installation Extension: SQL error processing request: DB function failed with error number 1062
Duplicate entry '1' for key 'PRIMARY'
SQL =
INSERT INTO `#__phocaguestbook_items` (`id`, `catid`, `parent_id`, `lft`, `rgt`, `level`, `path`, `username`, `userid`, `email`, `homesite`, `ip`, `title`, `alias`, `content`, `date`, `published`, `checked_out`, `checked_out_time`, `params`, `language`) VALUES
(1, 0, 0, 0, 1, 0, '', 'ROOT', 0, '', '', '', 'root', 'root', '', '0000-00-00 00:00:00', 1, 0, '0000-00-00 00:00:00', '', '*');"

[Jan]

Hi, what exactly do you not understand in this article:
https://www.phoca.cz/documents/16-jooml ... m-manually

Jan

[santinox]

Thanks for the reply.
When I log into phpmyadmin I did not understand what I have to do. I'm not a sql expert, I do not want to damage the database.
I do not know how I have to move within the phpmyadmin. I do not know what to click and how to do what that article says.
I need someone to explain it to me step by step, to avoid making mistakes that could compromise the entire database.

Example: I did not understand how to perform these operations:

-- 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%';

and this:
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%';

[santinox]

The problem is that I do not have those extensions in my database. The only items related to phocaguestbook are:
ucli2_phocaguestbook_items
ucli2_phocaguestbook_logging
There is nothing about phocapdf or "jos_xxxxxxxx extension"

[Jan]

Hi, all the tables: jos_extensions, jos_menu, etc. are Joomla! tables. Without such tables, Joomla! does not work.

Jan