Solved Succecfully installed but NO kunena at components

I don't understand.
Now I do'nt have any kunena files in my public HTML

How can I unpack and what do you mean?

maybe I wasn't quite clear.
So I did a test here on my Windows 10 PC. I also had my own domain tar.gz on my pc
So I put this in a new folder and just let it unpack windows 10 (winzip) and then you see the entire environment of your domain
as in my earlier attempt to explain this with the folders
but your backup may have a different structure think that may differ per hoster

I don't understand.
Now I do'nt have any kunena files in my public HTML

How can I unpack and what do you mean?

Copy the tar.gz file in an empty foder on your PC and unpack it.
Then navigate to administrator/components/com_kunena and open the kunena.xml and check the version (see image).
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Thank you very much!
I did as you suggested and it shows Kunena version 5.2.5.

Then why did I got error while upgrading Kunena?

 

Then why did I got error while upgrading Kunena?

Did you follow these steps?  www.kunena.org/docs/en/basics/upgrade/upgrade-k6-0

You can try this:
www.kunena.org/forum/k-6-0-support/16466...-duplicate-entry-com
But create a database backup first!
 

Thank you rich
If I follow the link you provided ( www.kunena.org/docs/en/basics/upgrade/upgrade-k6-0 )
But it shows me this (please see attachment):

Should I "Remove the kunena entries in the table #__mail_templates" as you mentioned in another post?