Joomla Extension Installation Error !

Its weeks I am searching Google and have test all the possible way suggested .
changing the permision of logs , tmp
adding extra script in .htaccess
editing folder.php
changing time zone taking the correct path using SSH from server and set on configuration file but still when i want to install extension like JCE getting the below error please help somebodyyyyy.
0 DateTime::__construct() [datetime.–construct]: Failed to parse time string (jerror) at position 0 (j): The timezone could not be found in the database
Answer #1
This error doesn’t seem to be related to any extension specifically, rather Joomla itself. Take a look at the following link. Have you tried changing the permissions of the plugins directory?
https://www.joomlacontenteditor.net/support/forum/installation-error-7