Plugins successfully uploaded via FTP but they are not on my site

Solution found.

In this case, the problem was the path name. It included a folder with a keyword that the server should reject: “worm”.

While for the template was not a problem, for the plugins folder it was.

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)