I just changed out the router I was using with another one, or to be more accurate, just changed the modem from being connected to one router to being connected to another. I was using multiple routers as switches (because I'd gotten them on sale over a period of time...)
I had been using the "wrong" IP address (i.e. something other than 192.168.0.1) on the router I was using as the actual router, and took the liberty of changing the "new" router to 192.168.0.1 and reconfiguring the machines here to point to there as the gateway machine.
Trouble is, now the SME machine cannot connect to the outside world, and when I, for instance, ping google.com I get "destination host unreachable," It even does that if I ping the IP address of the nameserver at my ISP.
I can't find in the Web-interface a place to change the address of the gateway machine. I changed the field for the DNS server from 192.168.0.3 (which is what it was bofore) to 192.168.0.1 but it is still giving me "destination host unreachable" for anything in the outside world.