v515w all in one inkjet printer - PRINT HEAD ERROR

I have followed all instructions in the manual - followed troubleshooting - but cannot get the error message out!! -"printhead error please refer to manual" - now i cant print, fax, copy etc....interestingly I cant even fax out!! It is not allowing me to do anything. Any help please?!! Is this covered under warranty? Can I get a replacement print head if required?? - I just bought this printer a few months ago!! Very very disappointed!! Thanks. Sally.