After installing the latest version of Joomla you may sometimes notice the below error in the “admin” section.

Error

An error occured

Screenshot:

Fix:

This happens because of the incorrect/low MySQL “sort_buffer_size”, to fix this edit the “my.cnf” file

vi  /etc/my.cnf

Add the below line to the end of the file

sort_buffer_size = 1M

Restart the MySQL server by executing

service   mysqld   restart

OR

service  mysql  restart

Now refresh the Joomla admin section and the error will not be displayed anymore.