canon pixma mp 520

hello,i just bought a canon pixma mp 520 and i 've tried to install it twice, following carefully the installation instructions, but eventhough it always sais that the installation is succesfully completed, when i try to print something it sais that it is executing another activity (which, from what i know, is not true). does anybody know why a printer appears to be busy, when in fact it has never been busy? i really don't understand.