So I recently moved my router from a 32 bit machine to an Amd64 machine, and switched from 32 bit ubuntu to 64 bit ubuntu.

One of the glitches I came across was that upnpd couldn’t register the root device.  I tracked the problem down to a bug with the upnp 1.4 library on x86_64.  I got pupnp-1.6.6 and compiled, installed, recompiled linux-igd, reinstalled that, and everything worked fine.

Hope this helps someone