unrecognized configuration parameter "autocommit"

I am testing an upgrade to a database from version 9.3 (this version is
working fine) to 9.5 and I am getting the following error:

*** unrecognized configuration parameter "autocommit" ***

I have read that I should set autocommit to off but I do not know how to do
it. I already reviewed all of the settings in the configuration file
(postgresql.conf) and I do not see such parameter.

I, in fact, found the following information in PostgreSQL documentation:
http://www.postgresql.org/docs/9.5/static/ecpg-sql-set-autocommit.html
but I do not know how to issue the command.

Does this issue gets solved setting autocommit to off?
If so, how do I set it?

I will appreciate if you provide some detail, I am not a DB expert, I only
connect toPostgreSQL from my application.

Best regards,
Jorge Maldonado