Returns a Inedo.Extensibility.UserDirectories.IUserDirectoryUser for the user with the specified user name and password.
The user name of the user to look up.
The password of the user.
A corresponding Inedo.Extensibility.UserDirectories.IUserDirectoryUser for the specified user name, if the user was found in the directory and the specified password is correct; otherwise null (Nothing in Visual Basic).
userName is null (Nothing in Visual Basic) or empty or password is null (Nothing in Visual Basic).