TYPO3 Core

The text reads:

Local configuration is done by overriding default values in the included file, typo3conf/LocalConfiguration.php. In this file you enter the database information along with values in the global array TYPO3_CONF_VARS.
The options in the TYPO3_CONF_VARS array and how to use it for your own purposes is discussed in the base configuration file, t3lib/stddb/DefaultConfiguration.php. This file sets up the default values and subsequently includes the localconf.php file in which you can then override values.

In the last sentence is the error:

This file sets up the default values and subsequently includes the localconf.php file in which you can then override values.

Please update localconf.php to LocalConfiguration.php.