I have exactly the same problem, but i think it's de rxtx library, try to uninstall it.
Few months ago i uploaded without problems, recently i installed MPIDE and I install rxtx library, the MPIDE works perfect, but arduino no.
I have exactly the same problem, but i think it's de rxtx library, try to uninstall it.
Few months ago i uploaded without problems, recently i installed MPIDE and I install rxtx library, the MPIDE works perfect, but arduino no.