[ Solved ] Could not connect to the database. Connector returned number: 2 - Error in Joomla 2.5 Installation

At the input of the basic settings at "Step 4 Database" of the Joomla 2.5 installation, it can happen, that the server reports:

"Could not connect to the database. Connector returned number: 2"

Possible Solution:

To solve this error, you should check, if you entered the right "Username" and the right "Password" in the "Basic Settings".