Oracle.DataAccess.dll is a .NET driver provided by Oracle Corporation that enables .NET applications to connect to Oracle Database. It provides a set of classes and interfaces for accessing and manipulating Oracle Database data from .NET applications. This driver can be used in various .NET technologies, including ASP.NET, ADO.NET, Windows Forms, and WPF.
The Oracle.DataAccess.dll file is required for any .NET application that uses the Oracle Data Provider for .NET to connect to an Oracle Database. If the file is missing or corrupted, the application will not be able to establish a connection to the database.