MySQL my.cnf file - Found option without preceding group

Missing config header

Just add [mysqld] as first line in the /etc/mysql/my.cnf file.

Example

[mysqld]
default-time-zone = "+08:00"

Afterwards, remember to restart your MySQL Service.

sudo mysqld stop
sudo mysqld start

Charset encoding

Check the charset encoding of the file. Make sure that it is in ASCII.

Use the od command to see if there is a UTF-8 BOM at the beginning, for example.